Determination of the estimated water flow. Determination of the estimated minimum water flow in the absence of hydrometric data Methodology for determining the minimum water flow in buildings

Determine Estimated Costs cold water(daily, m3/day; average hourly, m3/hour; maximum calculated second flow rate, l/s; maximum hourly flow rate, m3/hour) at the entrance to the building and select a water meter

Draw a schematic diagram of the water supply of the settlement. Describe the purpose of the main elements of the system

U hr \u003d 2.2 "n" t, (16)

We calculate the throughput of the pipe using an online calculator

What factors affect the permeability of the liquid through the pipeline

Section calculations according to SNIP 2.04.01-85

Settlement water supply device

Average hourly hot water consumption

Maximum hourly hot water consumption

For high-speed water heaters is determined by the formula

(3)

Formula for calculating pressure and pipe diameter: q = π × d² / 4 × V

Determining head loss

Task #2

Calculation costs and tariffs for services

Water supply and drainage (3)

Water supply and drainage residential building (3)

networks sewerage cities with a population of 63,010 inhabitants

(8)

6 EXAMPLES FOR DETERMINING THE ESTIMATED WATER COSTS AND

STOKOV

6.1 Example 1. Determination of the estimated water flow and cost

2 PRINCIPLES FOR DETERMINING THE ESTIMATED COSTS

Businesses and residential buildings consume a large number of water. These digital indicators become not only evidence of a specific value indicating consumption.

In addition, they help determine the diameter of the pipe assortment. Many people believe that it is impossible to calculate water flow by pipe diameter and pressure, since these concepts are completely unrelated.

But practice has shown that this is not the case. The capacity of the water supply network is dependent on many indicators, and the first in this list will be the diameter of the pipe range and the pressure in the line.

Perform calculation bandwidth pipes, depending on its diameter, are recommended even at the design stage of pipeline construction. The data obtained determine the key parameters of not only the home, but also the industrial highway. All this will be discussed further.

ATTENTION! To calculate correctly, you need to pay attention that 1kgf / cm2 \u003d 1 atmosphere; 10 meters of water column \u003d 1kgf / cm2 \u003d 1 atm; 5 meters of water column \u003d 0.5 kgf / cm2 and \u003d 0.5 atm, etc. Fractional numbers in the online calculator are entered through a dot (For example: 3.5 and not 3.5)

Enter parameters for calculation:

The criteria that affect the described indicator make up a large list. Here are some of them.

The inner diameter that the pipeline has.
The flow rate, which depends on the pressure in the line.
Material taken for the production of pipe assortment.

The determination of the water flow at the outlet of the main is carried out by the diameter of the pipe, because this characteristic, together with others, affects the throughput of the system. Also, when calculating the amount of fluid consumed, one cannot discount the wall thickness, the determination of which is carried out on the basis of the estimated internal pressure.

It can even be argued that the definition of "pipe geometry" is not affected by the length of the network alone. And the cross section, pressure and other factors play a very important role.

In addition, some system parameters have an indirect rather than a direct effect on the flow rate. This includes the viscosity and temperature of the pumped medium.

Summing up a little, we can say that the definition of throughput allows you to accurately set optimal type material for the construction of the system and make a choice of technology used to assemble it. Otherwise, the network will not function efficiently and will require frequent emergency repairs.

Calculation of water consumption by diameter round pipe, depends on it size. Therefore, over a larger cross section, a significant amount of fluid will move over a certain period of time. But, performing the calculation and taking into account the diameter, one cannot discount the pressure.

If we consider this calculation using a specific example, it turns out that less liquid will pass through a 1 cm hole through a 1 cm hole than through a pipeline reaching a height of a couple of tens of meters. This is natural, because the most high level water flow in the area will reach the highest rates at the maximum pressure in the network and at the highest values of its volume.

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First of all, you need to understand that the calculation of the diameter culvert is a complex engineering process. This will require specialized knowledge. But, when performing a domestic construction of a culvert, often a hydraulic calculation for the section is carried out independently.

This type of design calculation of the flow velocity for a culvert can be done in two ways. The first is tabular data. But, referring to the tables, you need to know not only the exact number of taps, but also containers for water collection (baths, sinks) and other things.

Only if you have this information about the culvert system, you can use the tables provided by SNIP 2.04.01-85. According to them, the volume of water is determined by the girth of the pipe. Here is one such table:

External volume of tubulars (mm)

The approximate amount of water that is received in liters per minute

Approximate amount of water, calculated in m3 per hour

If you focus on the norms of SNIP, then you can see the following in them - the daily volume of water consumed by one person does not exceed 60 liters. This is provided that the house is not equipped with running water, and in a situation with comfortable housing, this volume increases to 200 liters.

Definitely, this volume data showing consumption is interesting as information, but the pipeline specialist will need to define completely different data - this is the volume (in mm) and the internal pressure in the line. This is not always found in the table. And formulas help to find out this information more accurately.

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It is already clear that the dimensions of the system section affect the hydraulic calculation of consumption. For home calculations, a water flow formula is used, which helps to get a result, having data on the pressure and diameter of the tubular product. Here is the formula:

In the formula: q shows the flow of water. It is measured in liters. d is the size of the pipe section, it is shown in centimeters. And V in the formula is the designation of the speed of the flow, it is shown in meters per second.

If the water supply network is fed from a water tower, without the additional influence of a pressure pump, then the flow velocity is approximately 0.7 - 1.9 m / s. If any pumping device is connected, then in the passport to it there is information about the coefficient of the created pressure and the speed of the water flow.

This formula is not unique. There are many more. They can be easily found on the Internet.

In addition to the above formula, it should be noted that great value the functionality of the system is exerted by the inner walls of tubular products. For example, plastic products different smooth surface than analogues made of steel.

For these reasons, the drag coefficient of plastic is substantially lower. Plus, these materials are not affected by corrosive formations, which also has a positive action on the capacity of the water supply network.

The calculation of the passage of water is carried out not only by the diameter of the pipe, it is calculated by pressure drop. Losses can be calculated using special formulas. Which formulas to use, everyone will decide for themselves. To calculate the required values, you can use various options. the only one-stop solution this question is not.

But first of all, it must be remembered that the internal lumen of the passage of plastic and metal-plastic construction will not change after twenty years of service. And the inner lumen of the passage metal structure will become smaller over time.

And this will entail the loss of some parameters. Accordingly, the speed of water in the pipe in such structures is different, because in some situations the diameter of the new and old network will differ markedly. The amount of resistance in the line will also be different.

Also, before calculating the necessary parameters for the passage of a liquid, it must be taken into account that the loss of flow rate of a water supply system is associated with the number of turns, fittings, volume transitions, with the presence of valves and friction force. Moreover, all this when calculating the flow rate should be carried out after careful preparation and measurements.

The calculation of water consumption by simple methods is not easy to carry out. But, at the slightest difficulty, you can always seek help from specialists or use an online calculator. Then you can count on the fact that the laid water supply or heating network will work with maximum efficiency.

Calculation minimum expenses water on unexplored rivers or in the case when the available factual material is not suitable for use in calculations according to statistical formulas, is mainly done in two ways: according to maps of isolines of the minimum flow and according to empirical dependencies.

Contour maps are used in calculating the minimum 30-day flow of medium-sized rivers, with a catchment area from 1000 - 2000 (critical area) to 75 000 km 2. Rivers with a catchment area smaller than the critical one are classified as small rivers.

They have the magnitude of the minimum runoff module, which is different from the similar characteristics of medium-sized rivers. The method for determining the minimum runoff on small rivers is described below. The critical area shows the size of the basin area, starting from which there is practically no change in the modulus of the minimum 30-day runoff (M 30) with an increase in the basin area on the rivers of this region. (F). It is determined by constructing the dependence M 30 = f(F) on a biaxial logarithmic grid, on which the critical area will correspond to the inflection point of the curve when it passes into a straight line close to a horizontal line.

On the territory of Russia, 11 regions were identified in the winter season and 14 regions in the summer-autumn season, in which the rivers have critical basin areas close in size. Their value varies from 800 to 10,000 km 2. Therefore, to determine it in a given area, a map of areas (Fig. 4.3., 4.4.) can be used to determine the minimum 30-day water flow on small rivers and a table of the largest (critical) areas of small river basins (Table 4.3).

Table 4.3.

The largest critical basin areas (km 2 ) small rivers

District index on the map	Summer-autumn season	Winter season	District index on the map	Summer-autumn season	Winter season
BUT			D
B			E
AT			F
G

The method for determining the minimum 30-day runoff from contour maps is similar to the method for calculating the annual runoff. Minimum flow contour maps do not apply to lake rivers and rivers located in karst areas.

Minimum 30-day runoff on small rivers with a catchment area of at least 50 km 2, for humid areas and 100 km 2 for areas of insufficient moisture, is calculated from the empirical dependence of the type

where - the minimum 30-day water consumption, averaged over a long period, for the winter or summer-autumn seasons;

F- river basin area km 2;

a, n, with- parameters determined depending on the geographic location of the river are set according to the table and maps of the regions to determine the minimum 30-day runoff on small rivers (Table 4.4).

1 - boundary and index of the area to determine the largest value of the (critical) area of the small river basin; 2 - border and area number to determine the minimum 30 - day water flow for small rivers; 3 - district number and subdistrict index for determining the minimum 30 - day water discharges on small rivers; 4 - settlement sections

Rice. 4.3. Extracts from maps of areas to determine the minimum 30-day water flow on small rivers in the summer-autumn season.

1 - border and number of the region for determining the coefficient of variability; 2 – boundary and number of the area to determine the minimum average daily water flow;

Rice. 4.4. Copy from the map of areas to determine the minimum average daily water discharge and the coefficient of variability of the 30-day runoff in the summer-autumn season.

Table 4.4.

Parameter values a, n, c

District number on the map	serpent season	Summer - autumn season
a 10 3	n	with	a 10 3	n	with
	2,50	1,08		1,40	1,27
	1,60	1,05		0,94	1,24
	1,00	1,14		0,64	1,22
…
	0,012	1,30		0,0034	1,12	-500
	0,72	0,74	-300	0,15	1,05	-200
	0,24	0,90	-500	0,00013	1,93	-200
	1,10	0,85	-1000	0,053	1,06	-500
	0,87	0,84	-160	0,065	1,09

To calculate the minimum 30-day water consumption of various availability, the coefficient of variability Cv is determined depending on the value of the average multi-year minimum 30-day runoff module for the winter or summer-autumn season for a given area. As auxiliary material a map of areas is used to determine the coefficients of variability and a table of values Cv(Table 4.5.). The asymmetry coefficient is taken by analogy with the surrounding studied rivers or is assigned according to the ratio C S = 2Cv for humid areas and C s =1.0-1.5 Cv for areas of insufficient moisture.

Table 4.5.

Values Cv depending on the modulus of the minimum 30-day runoff for the summer and winter seasons

District number on the map	M winter month l / s from 1 km 2	C v winter months	M years. month l / s from 1 km 2	C v years. months
	0,5-3	0,3-0,2	3-12	0,5-0,3
	0-1	0,4-0,3	4-7	0,6-0,3
		__	2-4	0,6-0,4
	1,5-6	0,3-0,2	3-12	0,4-0,3
	1-5	0,4-0,2	1-7	0,5-0,3
	0,5-3	0,4-0,2	6-7	0,6-0,3
	1-5	0,7-0,3	1-5	0,6-0,3

The minimum water discharges of small rivers can be obtained from the dependence of the minimum 30-day runoff modulus with a 97% security on the thalweg mark of the river channel in the outlet, expressed in abs. m. for areas with the same hydrogeological conditions for feeding the river.

The value of the minimum average daily runoff is set by its ratio with the minimum 30-day runoff module according to the dependence

M day \u003d aM month - b,(4.2)

where M day- minimum average daily runoff module in l/s from 1 km 2. M months- minimum 30-day runoff module; a, b- parameters determined depending on the location of the river (Table 4.6.).

Table 4.6.

Parameter values a and b to determine the minimum average daily runoff module

District number on the map	serpent season	Summer - autumn season
a	b	a	b
	0,94	0,1	0,82	0,4
	0,86	0,1	0,74	0,1
	0,80	0,3	0,83
	0,70	0,4	0,72
	0,70	0,2	0,42
	0,75	0,1	0,47	0,1

Example 4.3. Determine the minimum 30-day and average daily water consumption of 90% security in the summer-autumn season of the river. Hurray at st. Ura-Guba (Kola Peninsula).

1. We establish that the area of the river basin up to the outlet is 1020 km2.

2. Based on the location of the river basin on the map (Fig. 4.3), we determine the index of the area and according to Table. 4.6 set the size of the area of the basin, to which the river is considered small (critical area). The value of the critical area for region A, in which the river basin is located. Hurray, is 1400 km2. Therefore, the calculation must be made according to the scheme used to determine the minimum runoff on small rivers.

3. Using the same map, we find that the number of the area to determine the minimum flow of a small river. According to the table 4.4 we determine the values of the parameters of the calculation formula for region 1, which are equal to a \u003d 0.0014, n \u003d 1.27, C \u003d 95. Substituting all the calculated parameters into formula 4.1, we obtain that the value of the average multi-year minimum 30-day water flow in the summer-autumn season is 9.85 m3/s, or 9.65 l/s per 1 km2.

4. To determine the coefficient of variability Cv on the map (Fig. 4.4), we establish that the basin of the river. Ura is located in region 1. According to the table. 4.5 we find that in region 1, the module value of 9.65 l / s from 1 km2 corresponds to the value of the coefficient of variability Cv, equal to 0.34 (the value of Cv is determined by interpolation, taking into account the fact that a larger value of the module corresponds to a smaller value of Cv).

5. The value of the coefficient of asymmetry Cs is taken in accordance with the recommendation for humid areas equal to 2 Cv

6. According to the established parameters Q = 9.85 m3/s, Cv = 0.34 and Cs =2 Cv, we determine that the calculated value of the minimum 30-day water consumption with 90% security is 5.3 mg/s.

7. To calculate the minimum average daily water consumption according to the equation, the map shown in fig. 4.4, according to which it is established that s. Ura is located in region 1, for which the regional parameters a and b are 0.82 and 0.4, respectively (the values of the parameters are determined from Table 4.6). The value of M 90%, equal to 5.2 l / s from 1 km 2, is substituted as the Mmes parameter. As a result of the calculation, we obtain that the required value of the minimum average daily water consumption (after the module is converted to water consumption) of 90% security is 3.94 m3/sec.

Example 4.4. Determine the minimum 30-day and average daily water discharges with a 75% supply in the summer-autumn season, a river on the Kola Peninsula in zone 3 (Fig. 4.3). We establish that the area of the river basin to the outgoing target is 920 km 2 .

Example 4.5. Determine the minimum 30-day and average daily water discharges with a 25% supply in the summer-autumn season, a river on the Kola Peninsula in zone 2 (Fig. 4.3). We establish that the area of the river basin up to the outlet is 1020 km2.

Maximum water flow

The maximum water discharges of rivers and small streams are understood as the highest annual values of instantaneous or urgent discharges observed during spring floods or rain floods.

On small watercourses with significant intraday fluctuations in levels and discharges, especially during rain floods, the peak of the flood may pass between the established observation periods. Therefore, urgent maximum costs are less than instantaneous ones. In turn, the average daily maximum is less than the urgent one. This difference is significant in very small streams and decreases with increasing catchment area of the river. Calculations should be made for instantaneous maximum water flows.

According to the genetic basis, or origin, the maximum water discharges are divided into:

a) formed mainly from the melting of snow on the plains,

b) from melting snow in the mountains and glaciers,

c) rain

d) from the combined action of snowmelt and rain - mixed maxima.

To the highs mixed ancestry include the maximum water discharges, in the formation of which it is impossible to establish the prevailing role of melt or rainwater.

When analyzing and calculating the maximum water discharges using the methods of mathematical statistics, the maxima of various genetic origins are considered separately.

The practical importance of the issue is determined by the fact that many elements of high water or floods must be taken into account in the construction of hydraulic structures. It is especially important to know the maximum water discharges of spring floods and rain floods, the size of which determines the size of the most massive structures - bridge crossings over rivers and small watercourses, a large number of which are annually built on automobile and railways ah, as well as the dimensions of spillways and culverts of other structures.

The correct determination of the maximum water flow and the operation of spillways depends on the uninterrupted operation of a structure or road, the safety or fate of the entire structure and objects adjacent to the river, as well as the cost of the structure. Inflated maximum water flow rates will increase the overall cost of the structure, which will reduce its economic efficiency. Underestimation of the maximum costs will lead to the destruction of the structure, flooding of the area adjacent to the river, material loss and human casualties.

The calculated annual probabilities of exceeding, or providing, the maximum water flow are determined depending on the capital class of the structure and are normalized by general technical guidelines recommended or mandatory for design organizations.

All hydraulic structures are divided into several classes according to their capital size. Buildings of high capital classes should serve several hundred years. In order for them to work smoothly, their spillways must be designed to pass the maximum flow of water of very rare frequency. Temporary hydraulic structures are calculated for the maximum water flow rates of more frequent occurrence.

Building codes and regulations [SNiP II–I 7–65] establish the following calculated annual probabilities of exceeding, or providing, the maximum water flow depending on the capital class of the structure:

Construction class ……..I II III IV

Р °/о……………………0.01 0.1 0.5 1

Temporary hydraulic structures of class V are calculated for the passage of maximum flow rates of 10% security.

Permanent culverts on highways are calculated for the maximum water discharges of the following resources:

Embankment edge……………………………1.0 2.0

Openings of bridges, pipes…………………1.0 2.0

Branched drainage systems………….....…2.0 4.0

embankment settlements,

entrance to mines, tunnels, etc.……………. 0.1 0.1

In this case, if the observed maximum flow rate has a probability of less than 1%, then it is taken as the calculated one.

Technical conditions for the design of railways provide for calculations of openings in bridges and pipes for the passage of the following costs:

a) the highest security of 0.33% for large and medium bridges and 0.2% for small bridges and pipes;

b) the estimated security specified below:

Construction class by degree of capitalization I I and II II

Flow rate, %.............................1 (for pipes 2) 1 (for pipes 2) 2

Depending on the degree of sufficiency (duration) of a series of observations and the reliability of the initial data, the following methods for calculating the maximum water discharges are used:

a) in the presence of a long series of hydrometric observations, an empirical probability curve is constructed, and top part extrapolated beyond the limits of observations to given probabilities using a theoretical probability curve;

B) in the presence of a short series of observations, insufficient for constructing security curves, but sufficient to bring it to a long series, the existing short series is reduced to a long series, and security curves are constructed from the latter;

c) in the presence of a short series of observations, insufficient to bring it to long period, as well as in the absence of observations on the settlement site, the calculation is made by indirect methods - by the analogy method or by formulas with provided parameters.

Determine the second and hourly water consumption for a residential building with centralized hot water supply with the number of apartments n sq. = 30 and the average occupancy V o = 4.5 people / m 2, the number of consumers U = V o n sq. = 4.5 30 = 135 people. Each apartment has the following sanitary equipment: bathtubs, 1700 mm long, washbasin, toilet bowl, sink.

1. Set the number of taps in the building

N tot \u003d N \u003d 4 * 30 \u003d 120;

2. In accordance with app. 3 SNiP 2.04.01-85* water consumption rates per consumer per hour of highest water consumption is:

q tot hr,u = 15.6 l/h; - general

q h hr,u = 10 l/h; - hot water

q c hr,u = 15.6 - 10 = 5.6 l/h. - cold water

3. According to the same table, the rate of water consumption by a sanitary appliance:

qtot o = 0.3 l/s (qtot o,hr = 300 l/h); - general

q c o = 0.2 l/s (q c o,hr = 200 l/h); - cold water

4. We determine the second probability of the action of devices according to the formula:

5. We find the value of the product NP and, according to Appendix 4 of SNiP 2.04.01-85*, the values of the coefficients b. Intermediate values b are found by exact interpolation.

N c P c \u003d 135 * 0.0078 \u003d 1.053 b c \u003d 0.99656;

NP = 1.05 b = 0.995

NP = 1.10 b = 1.021

6. Determine the maximum second flow of cold water:

q c = 5*q c o ? b c \u003d 5? 0.2? 0.99656= 0.99656 l/s;

7. Let's determine the hourly probability of the devices operation by the formula:

8. We find the value of the product NP hr and, according to Appendix 4 of SNiP 2.04.01-85*, the values of the coefficients b hr. Intermediate values of b hr are found by exact interpolation.

N c P c hr \u003d 135 * 0.028 \u003d 3.78; b c hr = 2.102288;

NP hr = 3.7 b = 2.102

NP hr = 3.8 b = 2.138

9. Determine the maximum hourly consumption of cold water in m3 / h according to the formula:

q with hr = 0.005*q with o,hr ? b with hr \u003d 0.005? 200? 2.102288 \u003d 2.102288 m 3 / h

10. From Appendix 3 of SNiP 2.04.01-85* you can find:

300 - 120 = 180 liters per day of peak consumption.

11. The average hourly consumption of cold water, m3 / h, for the period (day, shift) of maximum water consumption T, h, is determined by the formula:

q T = = = 1.0125 m 3 / h

For water supply of settlements, water is used from open reservoirs (rivers, lakes) or from underground sources. Water from open reservoirs contains pathogenic bacteria and various impurities, therefore, it requires cleaning and disinfection. Groundwater usually does not require such treatment. When designing water supply systems, the technical and economic requirements imposed on it are also taken into account: 1) ensuring the needs of the settlement in water during the hours of its maximum consumption; 2) the arrangement of main and intra-quarter water supply networks that provide water supply to all facilities put into operation; 3) low cost of water supplied to consumers; 4) creation of an operational service, the task of which is to ensure the required sanitary-hygienic and technical level of water supply to the settlement.

The intake of water from the river is usually carried out upstream (counting along the river) of settlements or industrial enterprises, which reduces the pollution of the water entering the water intake. Then it enters the coastal well 3 through a gravity pipeline 2 and is sent by pumps of the first lift 4 to settling tanks 5, where most of the suspended solids contained in it fall out of the water. Acceleration of the sedimentation process is achieved by adding coagulants to the water - chemicals that react with the salts contained in the water, resulting in the formation of flakes. The latter are quickly deposited in water and entrain suspended particles. Further, the water flows by gravity to treatment facilities 6, where it is first filtered through a layer of granular material (quartz sand) in filters, and then disinfected by adding liquid chlorine to it.

For this purpose, ozonation plants are used, which have a greater bactericidal effect and give water higher taste qualities than its chlorination (ozone is obtained from the air by means of electrical discharges).

Purified and disinfected water flows into reserve tanks 7, from where pumps of the second lift 8 pump water into the main conduits 9, the water tower 10 and then through the main 11 and distribution pipelines 12 water enters the buildings to consumers.

For the intake of underground water from aquifers, tubular wells are arranged - wells fixed with a column of steel pipes.

Above the well they make a superstructure in the form of a pavilion. In the lower part of the well, a filter is arranged through which water flows. The lifting of water is usually carried out by centrifugal pumps, which supply it to collection tanks or directly to the water supply network.

Water supply networks are made of steel, pressure, cast iron, reinforced concrete and asbestos-cement pipes. The equipment of these networks are valves that serve to turn off individual sections of the network in case of repair or an accident; fire hydrants, which serve to receive water through them to extinguish fires, and collapsible columns.

Household and drinking water pipelines with a pipe diameter of not more than 100 mm are allowed to be arranged as dead ends (in the form of a number of separate branches). With large diameters of the network, it is arranged with a ring, consisting of several closed rings (Appendix 1); the ring network provides uninterrupted water supply to all consumers even if it is damaged at any point.

ventilation building water supply sewerage

Task 3. Describe the devices of the internal sewer network, its structural elements, their purpose. Specify connecting shaped parts of sewer networks

The building is equipped with a centralized hot water supply system with hot water preparation in a water heater located in the basement.

Initial data:

Number of floors n floor =8;

Average occupancy of apartments U=2.5 people/sq.;

Water consumption norms:

total (cold and hot), per day of the highest water consumption
q u tot =300 l/day;

total, at the hour of the greatest water consumption l/h;

Cold
l/h;

Water consumption device:

general
;

cold
;

Floor height (floor to floor) 2.9m;

Plot lengths :

B - 1 = 2.1 m;

1 - 2 = 0.8 m;

2 - 3 = 1.4 m;

3 - 4 = 0.5 m;

4 - 5 = 2.9 m;

5 - 6 = 2.9 m;

6 - 7 \u003d 2.9 m;

7 - 8 = 2.9 m;

8 - 9 = 2.9 m;

10 - 11 = 2.9 m

11 - 12 = 4.3 m;

12 - 13 = 6.7 m;

13 - 14 = 7.0 m;

14 - 15 = 6.7 m;

15 - 16 = 7.0 m;

16 - 17 = 9.0 m;

Input = 17 m;

The difference between the floor marks of the first floor and the ground level at the point of connection of the input to the street water supply network () = 1.2 m;

Guaranteed pressure in the city water supply H=38 m. Art.

Rice. one

Decision:

To determine the costs in each settlement area, we calculate the probability of the operation of devices. For sections of cold water supply, the probability of operation of devices:

where
the rate of consumption of cold water by consumers in the hour of greatest water consumption;

U – number of water consumers:

U= un sq. n this ,

here u- average occupancy of apartments, persons/sq.;

n kv - the number of apartments on the floor, equal to the number of risers;

q 0 s - normative consumption of cold water by the dictating water folding device;

From the expression we get:

U=2.5∙8∙8=160 people;

N- the number of taps in the building:

N= n sq. n etc n this ,

here n pr - the number of water folding devices in one apartment.

N=4∙8∙8=256.

Then from the expression we get:

For common areas, the value of p tot determined by the formula

where is the total rate of water consumption, l/h;

total standard water consumption by one device, l / s.

We determine the water flow in each area according to the formula:

where q 0 - standard water consumption by the device;

α is a dimensionless coefficient depending on the amount of water
ny devices on the given site and probability of their action.

Using Appendix 1. determine the valueα for each calculation area for the productNP and the corresponding maximum water flowq c orq tot .

Plot 17-18:

N = 256; NР = 256 ∙ 0.009 = 2.30 => α = 1.563;

q 17-18 = 5 q 0 tot ∙ α = 5 ∙ 0.3 ∙ 1.563 = 2.341 l/s;

Section 16 - 17:

N = 256; NP \u003d 256 ∙ 0.009 \u003d 2.3 \u003d\u003e α \u003d 1.563;

Q 15-16 = 5 q 0 c ∙ α = 5 ∙ 0.3 ∙ 1.563 = 2.341 l/s;

Section 15 - 16:

N = 4 ∙ 8 ∙ 8 = 256; NP \u003d 256 ∙ 0.00486 \u003d 1.244 => α \u003d 1.093;

Q 14-15 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 1.093 = 1.093 l/s;

Plot 14 - 15:

N = 4 ∙ 6 ∙ 8 = 192; NP \u003d 192 ∙ 0.00486 \u003d 0.933 => α \u003d 0.933;

q 13-14 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.933 = 0.933 l/s;

Plot 13 - 14:

N = 4 ∙ 4 ∙ 8 = 128; NP \u003d 128 ∙ 0.00486 \u003d 0.622 => α \u003d 0.756;

Q 12-13 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.756 = 0.756 l/s;

Plot 12 - 13:

N = 4 ∙ 2 ∙ 8 = 64; NP \u003d 64 ∙ 0.00486 \u003d 0.311 => α \u003d 0.543;

Q 11-12 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.543 = 0.543 l/s;

Plot 11 - 12:

N = 4 ∙ 1 ∙ 8 = 32; NP \u003d 32 ∙ 0.00486 \u003d 0.156 => α \u003d 0.406;

Q 10-11 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.406 = 0.406 l/s;

Section 10 - 11:

N = 4 ∙ 1 ∙ 7 = 28; NP \u003d 28 ∙ 0.00486 \u003d 0.136 => α \u003d 0.383;

q 9-10 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.383 = 0.383 l/s;

Section 9 - 10:

N = 4 ∙ 1∙ 6 = 24; NP \u003d 24 ∙ 0.00486 \u003d 0.117 => α \u003d 0.363;

q 8-9 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.363 = 0.363 l/s;

Section 8 - 9:

N = 4 ∙ 1 ∙ 5 = 20; NP \u003d 20 ∙ 0.00486 \u003d 0.097 => α \u003d 0.340;

q 7-8 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.340 = 0.340 l/s;

Section 7 - 8:

N = 4 ∙ 1 ∙ 4 = 16; NP \u003d 16 ∙ 0.00486 \u003d 0.078 \u003d\u003e α \u003d 0.315;

q 6-7 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.315 = 0.315 l/s;

Section 6 - 7:

N = 4 ∙ 1 ∙ 3 = 12; NP \u003d 12 ∙ 0.00486 \u003d 0.058 => α \u003d 0.286;

q 5-6 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.286 = 0.286 l/s;

Section 5 - 6:

N = 4 ∙ 1 ∙ 2 = 8; NP \u003d 8 ∙ 0.00486 \u003d 0.039 \u003d\u003e α \u003d 0.254;

q 4-5 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.254 = 0.254 l/s;

Section 4 - 5, 3 - 4:

N = 4 ∙ 1 ∙ 1 = 4; NP \u003d 4 ∙ 0.00486 \u003d 0.019 => α \u003d 0.213;

q 4-5 = q 3-4 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.213 = 0.213 l/s;

Section 2 - 3:

N = 3; NP \u003d 3 0.00486 \u003d 0.015 \u003d\u003e α \u003d 0.202;

q 2-3 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.202 = 0.202 l/s;

Plot 1 - 2:

N = 2; NP \u003d 2 ∙ 0.00486 \u003d 0.01 \u003d\u003e α \u003d 0.200;

q 1-2 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.2 = 0.2 l/s;

Plot B-1:

N = 1; NP \u003d 1 ∙ 0.00486 \u003d 0.00486 \u003d\u003e α \u003d 0.200;

q IN 1 = 5 q 0 with ∙α = 5 ∙ 0.2 ∙ 0.2 = 0.2 l/s.

Let us determine the head loss along the length of each calculated section according to the formula

where l- the length of the calculated section.

h B -1 \u003d 360.5 ∙ 2.1 / 1000 \u003d 0.757 m;

h 1-2 \u003d 360.5 ∙ 0.8 / 1000 \u003d 0.288 m;

h 2-3 \u003d 368.5 ∙ 1.4 / 1000 \u003d 0.516m;

h 3-4 \u003d 412.5 ∙ 0.5 / 1000 \u003d 0.206 m;

h 4-5 \u003d 412.5 ∙ 2.9 / 1000 \u003d 1.196 m;

h 5-6 \u003d 114.1 ∙ 2.9 / 1000 \u003d 0.331m;

h 6-7 \u003d 142 ∙ 2.9 / 1000 \u003d 0.412m

h 7-8 \u003d 170.4 ∙ 2.9 / 1000 \u003d 0.494m;

h 8-9 \u003d 196.1 ∙ 2.9 / 1000 \u003d 0.569m;

h 9-10 \u003d 221.8 ∙ 2.9 / 1000 \u003d 0.643m;

h 10-11 \u003d 245.5 ∙ 2.9 / 1000 \u003d 0.712m;

h 11-12 \u003d 274.1 ∙ 4.3 / 1000 \u003d 1.179;

h 12-13 \u003d 129.5 ∙ 6.7 / 1000 \u003d 0.868;

h 13-14 \u003d 55.7 ∙ 7 / 1000 \u003d 0.390 m;

h 14-15 \u003d 82.3 ∙ 6.7 / 1000 \u003d 0.551m;

h 15-16 \u003d 110.6 ∙ 7 / 1000 \u003d 0.774m;

h 16-17 \u003d 61.6 ∙ 9 / 1000 \u003d 0.554m;

h cc =61.6∙17/1000=1.047m.

The entire calculation of the internal water supply is reduced to the calculation table

Hydraulic calculation of the internal water supply

Account number
site

The number of water taps in this area,N , PCS.

Estimated consumption on the site q, l/s

Pipeline diameter d, mm

Calculated section length l, m

Water speed V, m/s

hydraulic slope i

Head loss along the length of the section h l, m

The sum of the head loss along the length

7.024 m

h BB \u003d 0.306 m

After determining the estimated flow rates, a water meter should be selected. To do this, it is necessary to calculate the estimated water consumption: maximum daily, average hourly and maximum hourly.

Maximum daily water consumption (m 3 /day) for the needs of cold and hot water supply is determined by the formula

whereq u t about t - the general rate of water consumption by the consumer per day of the highest water consumption, l;

U - the number of water consumers.

Average hourly water consumption
, m 3 /h, per day of maximum water consumption

Maximum hourly water consumption, m 3 /h, for the needs of cold and hot water supply:

where
- total water consumption, l / h, sanitary fixture;

- coefficient determined by adj. 1 depending on the value of the product NP hr (N- the total number of sanitary - technical devices serviced by the designed system, P hr- the likelihood of their use).

The probability of using sanitary appliances for the system as a whole is determined by the formula

NP hr =256∙0,032=8,192;

According to Appendix 1 α hr =3,582;

According to Appendix 4, we select a high-speed water meter with a nominal diameter of 40 mm (hydraulic resistance of the meter s = 0.51).

After choosing a water meter, the pressure loss in it should be determined. Loss of pressure in the water meterh waters , m, is determined by the formula

h waters = sq 2 =0,51∙1,49 2 =1.13 m,

where q is the flow rate of water flowing through the water meter, l/s.

We determine the amount of pressure required to supply the standard water flow to the dictating water-folding device at the highest household and drinking water consumption, taking into account the pressure loss to overcome resistance along the path of water movement.

where H G - the geometric height of the water supply from the point of connection of the input to the external network to the dictating water folding device:

where H this- floor height;

n this- number of floors;

l in 1- the length of the first calculation section (the height of the location of the dictating calculation point above the floor level);

h centuries - loss of pressure in the input;

h waters- loss of pressure in the water meter;

The sum of pressure losses along the length of the calculated sections;

1,3 - a coefficient that takes into account pressure losses in local resistances, which for residential and drinking water supply networks public buildings taken in the amount of 30% of the pressure loss along the length;

H R- working standard pressure at the dictating water folding device (for a bath with a mixer H R=3 m).

H G \u003d 2.9 (8-1) + 1.2 + 2.1 \u003d 23.6 m;

H tr\u003d 23.6 + 0.306 + 1.13 + 1.3 ∙ 7.024 + 3 \u003d 3.167 m.

H tr=37.167 m<H G\u003d 38 m, therefore, a booster pumping unit is not required.

Determine the maximum estimated flow cold water q c , l / s, in the drinking water supply system of an industrial enterprise, in a single unit, which has:

a) a workshop with heat emissions less than 84 kJ per 1 m 3 / h;

b) household premises with group showers;

c) canteen with a full cycle of cooking.

The building has a centralized hot water supply system.

The consumption rates of cold water by various consumers are given in Table 2.

Initial data:

Decision:

Let us determine the probabilities of the operation of devices in each group of water consumers: R with I , P c II , P c III. For the II group of consumers (shower nets) we will take P c II =1 , since all showers can be turned on at the same time after the end of the shift in the workshop. Quantities R with I andP c III determined by the formula

where
- the rate of water consumption per hour of the highest water consumption by the consumer of the group i(accept according to Table 2);

U i- the number of consumers in group i (initial data);

- second consumption of cold water, l / s, by water fittings for each group of water consumers (accept according to Table 2);

N i- the number of water-folding devices serving a group of water consumers.

;

Let us determine the weighted average value of the second flow rate of cold water by water fittings, related to one device, determined by the formula

Let us determine the coefficient α by adj. 1, with total number of appliancesNand their probabilities
( determined by the formula)

N=53+40+14=107;

NP=107∙0.4=42.8 => α=12.6.

Let's determine the maximum design flow rate of cold water using the formula

q c = 5 q c o α \u003d 5 ∙ 0.1385 ∙ 12.6 \u003d 8.73 l / s.

Answer: q c = 8.73 l/s.

Task #3

A group of the same type of n-storey residential buildings is supplied with water from a central heating point connected by an input pipeline to the street water supply network. Cold water from the street network through the input enters the central heating unit, in which a high-speed water heater is installed. Part of the cold water passes through the water heater and enters the hot water supply system of buildings, the other part enters the cold water supply system.

Each apartment has four water-folding devices (washbasin, sink, bathtub with a shower net and a toilet bowl with a flush barrel).

Determine the estimated water consumption for a heating point (for the needs of cold and hot water supply), select a water meter installed at the input to the heating point, calculate the average and maximum hourly consumption of hot water by a group of buildings; make the necessary calculations and choose the brand of the water heater.

Regulatory second and hourly consumption of water by a water-folding device should be taken:

q = 0.3 l/s q=300 l/h

q = 0.2 l/s q = 200 l/h

Initial data:

Number of buildings of the same type n zd
Number of floors n this
Number of apartments per floor n sq.
Average occupancy of apartments U person/sq.
The rate of water consumption per day of the highest water consumption: General q , l hot q , l
The rate of water consumption per hour of the highest water consumption: Total q , l hot q , l
Initial coolant temperature, With coolant end temperatures С

The solution of the problem.

The maximum daily water consumption by a heating unit for the needs of cold and hot water supply of buildings is determined by the formula:

Q=0.001 q U where,

Number of water users U= u n sq n floor n zd

u - average occupancy of apartments

n sq - number of apartments

n floor - number of floors

n zd - number of buildings

U = 3,0 ∙ 4 ∙ 6 ∙ 6 = 432

Q \u003d 0.001 ∙ 300 ∙ 432 \u003d 129.6 m 3 / day

The average hourly water consumption per day of maximum water consumption is determined by the formula:

q = Q/24

q = 129.6 / 24 \u003d 5.4 m 3 / h

Maximum hourly water consumption for the needs of cold and hot water supply:

q = 0.005 q ∙
where

q- total water consumption l / h, sanitary fixture;

The coefficient determined from Appendix 1 (working program and assignments for test 23/10/2) depending on the value of the product N P (N is the total number of sanitary appliances served by the designed system, P is the probability of their use).

P hr =
for common areas, the value P determined by the formula

P =
,

Where q is the total rate of water consumption (cold and hot), l, by the consumer at the hour of the highest water consumption.

q - total normative water consumption by one consumer, l/s.

N = n pr n floor n r n apt

Here n pr is the number of water fittings in one apartment

N= 4 ∙ 6 ∙ 6 ∙ 4= 576

P = =0,0108

P hr =
=0,0389

N P = 576 ∙ 0,0389 = 22,4

7.5 from application 1

q = 0.005 ∙ 300 ∙ 7.5 \u003d 11.25 m 3 / h

According to the calculated values of the estimated water consumption, guided by Appendix 4 (23/10/2),

you need to choose a brand of water meter

Total maximum second water consumption by a group of buildingsq

=5∙ ,

where,
- coefficient determined according to Appendix 1 depending on the value of the product N P

N P = 576∙0,0108 = 6,22

= 2,962

5∙0.3∙2.962= 4.44 l/s

calculate the pressure loss in the water meter

where s is the hydraulic resistance of the meter, taken according to Appendix 4 (23/10/2)

q- water flow through the water meter l/s

h = 0.142 ∙ 4.44 2 \u003d 2.8 m,

where - hot water consumption rate, l, by the consumer per day of the highest water consumption

U is the number of hot water consumers

T is the number of hours in a day (T = 24h).

q
= 2.16m 3 /h

q = 0.005 q ∙

where q is the standard consumption of hot water by a water-folding device

The coefficient determined according to Appendix 1 depending on the value of the product N P (N is the total number of sanitary appliances served by the hot water supply system, P is the probability of their use).

P hr =

where is the probability of operation of sanitary appliances in the hot water supply system

- normative consumption of hot water, l / s, by a sanitary appliance.

where is the standard consumption of hot water, l, by the consumer in the hour of the highest water consumption

N - the number of water folding devices serving the hot water supply system

N = n pr n floor n r n apt

= 0,0104

P hr =
= 0,0374

N P = 576 ∙ 0,0374 = 21,54

q = 0.005 ∙ 200 ∙ 7.282 \u003d 7.282 m 3 / h

Estimated heat consumption for the preparation of hot water during the hour of maximum water consumption

Q= 1,16 q(55- t)+ Q

where t- temperature of cold water, o C, in the water supply network (taken equal to 5 o C)

Q- heat loss by falling and circulation pipelines of the hot water supply system

Heat loss can be taken into account approximately by the formula

Q= Q k,

where Q- average hourly heat consumption for hot water supply

k - coefficient taking into account heat losses by pipelines (we take k = 0.35)

125.28 kW,

Q= 125.28 ∙ 0.35 = 43.85 kW

Q \u003d 1.16 ∙ 7.282 (55-5) + 43.85 \u003d 466.206 kW

According to the condition of the problem, the preparation of hot water is carried out in a high-speed water heater installed in the central heating point.

In high-speed water heaters, the consumed water flows at a high speed of 0.5-2.5 m/s. Due to this, they have high heat transfer coefficients, and therefore are very compact and occupy a small area.

It is advisable to carry out the calculation in the following order.

Given the speed of movement of the heated water v n.v. in the aisles of 0.5-2 m / s, we determine the required cross-sectional area of \u200b\u200bthe water heater tubes f mp, based on the maximum hourly flow rate of hot water q

f mp =

I accept v n.v. = 1.5 m/s

f mp =
\u003d 0.00135 m 2

using appendix 6, we select a water heater, according to the closest to the calculated value of the cross-sectional area of the tubes.

fmp \u003d 0.00185 m 2

after which, for the selected brand of water heater, we calculate the speed of movement of the heated v n.v. and heating v gv water.

where
- cross-sectional area of the annular space through which the heating water flows

t n, t k - initial and final temperatures of the coolant

- water density (= 1000kg / m 3)

С – heat capacity of water (С=4.19 kJ/kg deg)

0.00287 m 2 - based on app. 6

We calculate the speed of movement of heated water

=1.093 m/s

Heating water speed

=1.292 m/s

According to the calculated values of v n.v and v gv, using Appendix 7, we find the value of the heat transfer coefficient of the heating surface (K) With sufficient pressure in the external network, the high-speed heater is considered poorly selected if K 1700 W / m 2 deg In this case, a smaller heater should be taken, which will have higher flow rates of heated and heating water, and, consequently, a higher K value.

K= 1943.2

The required heating surface of water heaters is determined by the calculated hourly heat consumption and the heat transfer coefficient.

where - correction factor taking into account the presence of scale on the heater pipes (=0.6 - for steel pipes, = 0.75 - for brass pipes)

- estimated temperature difference between the coolant and heated water

where b, m are the larger and smaller temperature difference between the heat carriers and the heated water at the ends of the water heater.

Most often, a high-speed water heater works according to a counterflow scheme (cold water meets the cooled coolant, and heated water meets hot).

B \u003d t n - t g (or t to -t x)

M \u003d t to - t x (or t n - t g)

where t n and t k - initial and final temperature of the coolant

t g and t x initial and final temperature of the heated water (t x = 5, t g = 75
)

M = 90-75=15

Determine the required heating surface of water heaters

= 666.4 m 2

We calculate the value of the required heating surface of the water heater, determine the required number of heater sections

where - the required number of sections of the adopted water heater (rounded up to the nearest whole number of sections)

- heating surface area of one section (we take from appendix 6)

=298 sec.

Task #4

Make a hydraulic calculation of the yard sewer network that drains wastewater from a residential building to the city network, according to a given version of the general plan.

The surface of the land is horizontal.

Initial data	Variant number
Initial data
Variant of the master plan of the yard sewerage
*Number of taps in the building N
*Number of inhabitants U
* consumption rate of cold and hot water at the hour of the highest water consumption q l
Ground elevation
Elevation of the pipe tray of the yard sewer network in the first well
Elevation of the city sewer pipe tray
Section lengths:

The master plan provides a yard sewer network of a residential building. Waste liquid through outlets from the building flows by gravity into the yard network. The number of releases is one. Each issue ends with a manhole. In addition, a control sewer well (KK) is installed on the red line, in which, if necessary, a drop is arranged. For inside the quarterly sewer network, pipes with a diameter of at least 150 mm are used.

K1 - yard sewer-

well

KK - control sewer well.

GKK - city sewer

ration well

The main purpose of the hydraulic calculation of the yard sewerage network is to select the smallest pipe slope, which ensures the passage of the estimated flow rate of the waste liquid at a speed of at least 0.7 (speed of self-cleaning). At a speed of less than 0.7, the deposition of solid cock and clogging of the sewer line is possible.

It is desirable that the yard network has the same slope throughout. The smallest slope of pipes with a diameter of 150 mm is 0.008. The greatest slope of the pipes of the sewer network should not exceed 0.15. at the same time, the filling of pipes must be at least 0.3 diameters. Permissible maximum filling of pipes with a diameter of 150 - 300 mm is not more than 0.6.

Hydraulic calculation should be made according to the tables, assigning the fluid velocity v, m / s and filling h / d in such a way that the following condition is met in all sections:

v
0,6

Design area number

Section length, m

Quantity sanitary appliances in this section N, pcs.

Total consumption of cold and hot water in the design area q tot l/s

Waste liquid flow rate in the calculated section q s l/s

Pipe diameter d, mm

Pipe slope, i

Waste fluid flow rate, v, m/s

Pipe filling, h/d

Elevation of pipe trays in sections, m

The difference in the marks of the trays on the site, m

q Calculation of the population of the city 2. Calculation ... by an indicator of the correctness of the choice them diameters. Network...

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... (tariffs) for services water supply and sewerage Tariffs (prices) for services water supply and sewerage developed in companies... general scheme water supply. The sequence of location of individual structures of the system water supply and them composition can...

Abstract >> Geology

Sanitary protection strip (SZP), respectively them purpose, established special mode and determined by... water quality. Calculation ZSO Calculation belts depends on the specific source water supply, hydrogeological conditions...

Abstract >> Construction

... water supply buildings 5 Water supply inlet 5 Water metering unit 5 Features of the arrangement of internal water supply networks 5 2 Calculation... subject to availability them joint transportation and ... in places convenient for them service. On underground pipelines...

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Energy Construction Department " Water supply and sewerage" Explanatory note to the exchange rate ... from the amount of expenses, them values are defined for... calculation household: ; From this point calculation we keep in tabular form table 4. Calculation ...

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OJSC SANTEKHNIIPROEKT

MANUAL FOR DETERMINING THE ESTIMATED WATER COSTS IN THE SYSTEMS OF WATER SUPPLY AND SEWERAGE OF BUILDINGS AND Neighborhoods

The material was developed by the creative team of SantekhNII-proekt JSC as a manual when using the organization standard STO 02494733 5.2-01-2006 "Internal water supply and sewerage of buildings".

The Handbook discusses the main issues of determining the estimated water and wastewater consumption, provides the methodological foundations of mathematical models of water consumption, as well as specific examples of calculating the values of water and wastewater consumption, tables of the necessary initial data for water supply and sewerage systems of buildings for various purposes.

Developers

QY. Dobromyslov! cand. tech. Sciences (JSC "SantekhNIIproekt")

A.S. Verbitsky, Ph.D. tech. Sci., A.L. Lyakmund (MosvodokanalNIIproekt)

1 Introduction 3

2 Principles for determining estimated costs 4

3 Statistical methodology for determining the estimated flow 7

4 Determination of estimated water and waste flows 11

Initial data and the procedure for determining the calculated races - ^

water and waste flows 6 Examples of determining the estimated flow of water and waste 20

4 DETERMINATION OF THE ESTIMATED WATER AND EFFLUENT COSTS

4.1 For the hydraulic calculation of water supply systems and the selection of equipment, the following water flow rates are used:

Estimated average daily consumption (total, hot, cold) for the estimated time of water consumption (T), m 3 / day, (see 4.2);

Estimated maximum daily costs (total, hot, cold), m 3 / day, (see 4.6);

Estimated maximum hourly flow rates (total, hot, cold), m 3 / h, (see 4.4);

Estimated average hourly costs (total, hot, cold), m 3 / h, (see 4.3);

Estimated minimum hourly costs (total, hot, cold), m 3 / h, (see 4.5);

Estimated maximum flow rates per second (total, hot, cold), l/s, (see 4.4);

Estimated maximum flow rates per second for circulation in hot water systems, l/s, (see 4.6).

4.2 Estimated average daily water consumption, m 3 / day, for the j -th estimated section of the water supply system is determined by the formulas:

cold

ChtgЪО.t, And

general (total - cold and hot water)

where i - consumers, to which water is supplied through the j-th estimated section of the water supply network;

Qji. Q "ti - Q" r "i ‘ calculated average daily water consumption (cold, hot, general) for various types of consumers are determined according to tables A2 and AZ (Appendix A).

Note - For each group of homogeneous (identical) consumers in formulas (1-3), the summation should be replaced by multiplying the calculated average daily costs for one consumer by the number of consumers.

4.3 Estimated average hourly water consumption, m 3 / h, for the j -th estimated section of the water supply system are determined by the formulas:

cold

hot 4=14- (5)

where I - consumers (including sanitary appliances), to which water is supplied through the j -th settlement section of the water supply network;

q Tj - estimated average hourly consumption of water / consumer or

sanitary appliance, l / h, is taken according to table A.1 for various devices or equal (Qn / Ti) for different consumers, Q T values are taken according to tables A.2 or A.3;

Ti is the duration of the period for which the Qji values are set in Table A.3.

Note - For each group of homogeneous (identical) consumers in formulas (4) - (6), the summation is replaced by multiplying the calculated average hourly costs for one consumer by the number of consumers.

4.4 Calculated maximum hourly (q ™, q ^), m 3 / h, and

calculated maximum seconds (q tot , q h , q c), l/s, water flow

for design sections of cold and hot water supply networks are taken according to tables A.4 (Appendix A).

The specified maximum estimated costs in water supply networks are determined depending on:

a) average specific estimated hourly water consumption

(^hr nd ’ q hr ud" q hr iid"*" l ^ 4, 0P

an even average hourly flow rate (found according to 4.3) in the calculated section of the network for the total number of sanitary appliances (N) or consumers (U) to which water is supplied;

b) the number of sanitary appliances or the number of water consumers (N - for the water supply system as a whole and for individual sections of the design scheme of the water supply network).

With an unknown number of sanitary fixtures / water points, it is allowed to take the number of fixtures equal to the number of consumers - N=U.

For residential multi-apartment buildings, the maximum hourly and second water consumption for the calculated sections of cold and hot water supply networks can be determined from tables A.b - A.9 (Appendix A) depending only on the number of apartments (n), to which water is supplied according to the calculated network section. When using tables A.b -A.9, the estimated average daily water consumption (l / day per person) should be taken from table A.2 for residential buildings with various systems engineering support, taking into account climate zone building construction.

Estimated water consumption in hot water pipeline networks is determined by:

For the maximum drawdown mode, it is similar to the cold water flow rates with the addition of a residual circulation flow in the network sections from the heating point to the first drawdown point;

For the circulation mode, taking into account section 11, STO 5.2-01.

4.5 Estimated minimum hourly flow rates of cold and hot water, m 3 / h, are determined by the formula

q u =q>K . , (7)

where K min ~ is taken from table 1 depending on

values K \u003d - w -.

Note - In formula (7), the value q T is taken equal to

q T , or q T , or q T , and q hr values correspond to either q hr , or q c hr , or Qhr . respectively.

Table 1

4.6 The calculated maximum daily water consumption (m 3 / day) in the networks of cold and hot water pipelines are taken equal to the product of the calculated average daily water consumption (determined in accordance with 4.2) and the coefficients of the maximum daily unevenness, which should be taken from Table A.5 (Appendix A) depending on the values of the calculated average hourly water consumption for sections of the water supply networks (determined in accordance with 4.3) and the number of sanitary fixtures / points of water intake or the number of consumers.

4.7 For risers of sewerage systems, the calculated flow rate is the maximum second flow rate of drains (q s, l / s), from those connected to

riser of sanitary appliances, which does not cause the failure of hydraulic valves of any types of sanitary appliances (receivers Wastewater). This flow rate is determined as the sum of the calculated maximum second flow rate of total water (totally cold and hot) for all sanitary appliances ^ (determined in accordance with the requirements of 4.3) and the calculated maximum second flow rate qft 1 from the device with maximum drainage (as

as a rule, is taken equal to 1.6 l / s - flow from flush tank toilet) according to the formula

4.8 For horizontal outlet pipelines of sewerage systems, the calculated flow rate is q sL, l / s, the value of which

is calculated depending on the number of sanitary fixtures N connected to the designed pipeline section and the length of this pipeline section L, m, according to the formula

where K is the coefficient taken according to table 2;

qo s 2 - wastewater flow from the device with maximum capacity, l / s.

For a residential building (residential apartment) q 0 s2 is assumed to be 1.1 l / s - the flow rate from a fully filled bath with a capacity of 150 - 180 l with a release of 0 40-50 mm.

table 2

Values k s at L, m

Note - The length L is taken as the distance from the last riser in the calculated section to the nearest connection of the next riser or, in the absence of such connections, to the nearest sewer well

5 INITIAL DATA AND PROCEDURE FOR DETERMINING THE ESTIMATED WATER AND EFFLUENT COSTS

5.1 Determination of the estimated water and wastewater flow rates should be made on the basis of the customer's initial data, which should include:

Average specific water consumption (per year, day, shift, etc.) for all water consumers (product units) and/or sanitary appliances;

Number and type of sanitary appliances or water consumers (product units).

5.2 Estimated average specific (for a year, day, shift) water consumption should be taken taking into account the data provided by the customer on the actual water consumption at analogue facilities, taking into account the measures and technical solutions provided for by the project to prevent irrational use and loss of water.

5.3 In the absence of the data provided for in 5.1 and 5.2, the approximate values of the specific average daily daily water consumption per year should be determined in accordance with the data in Appendix A - for residential buildings according to table A.2, for other types of objects according to table A.3, for various types sanitary equipment - according to table A.1.

5.4 For sections of the cold water supply network, through which water is supplied to the flush taps, the calculated maximum second flow rate is determined as the sum of the flow rate determined in accordance with 4.4 and the second flow rate of the flush tap (Table A.1, column 9).

5.5 Estimated water consumption for sections of water supply networks in the premises of group shower installations (only for sections of the network through which water flows to shower nets, excluding other sanitary appliances) are calculated by the formulas:

Estimated maximum hourly consumption of common, cold and hot water:

qZ \u003d Q.5N e, m 3 / h (10)

q hr \u003d 0.23W, m 3 / h (11)

q "hr \u003d 0.27A r g, m 3 / h (12)

Estimated maximum second consumption of common, cold and hot water:

q°" = 0.2N e , l/s (13)

q c = 0,\2N e , l/s (14)

q = 0.12N g , l/s (15)

where L / in - the number of shower nets.

5.6 Estimated maximum hourly and second consumption of cold and hot water for sections of water supply networks, for which

water is supplied to group shower installations, and also for the facility as a whole are determined as the sum of per capita flow rates determined by formulas 10-15 and the estimated water flow rates calculated in accordance with 4.4, while the latter should be determined without taking into account water flow rates in shower installations.

5.7 The number of meals and hours of work in public establishments

power supply should be taken according to technological data (according to the design assignment). With unknown productivity of catering establishments, the average number of dishes - , produced in 1 hour

the work of the enterprise, it is allowed to determine by the formula

where n is the number of seats;

m - the number of landings per hour, taken for open-type canteens and cafes equal to 2; for public catering establishments at industrial enterprises and student canteens equal to 3; for restaurants -1.5.

The estimated performance of a public catering enterprise (U hr - the maximum hourly number of dishes prepared) should be determined by the formula

Uhr = 1.5C7 Lg (17)

5.8 For individual rooms hospitals and sanatoriums (in the absence of other data) are allowed to accept:

a) the duration of the work of units and the use of water:

Food unit -9 hours;

Buffet attendants- 2 h;

Buffet in the departments of the hospital - 1 hour after a meal.

b) the daily amount of meals consumed by one person:

1 patient - 5 meals;

1 employee in the department - 2.2 meals.

5.9 In the absence of other data in the design assignment for general education schools, vocational schools

and pioneer camps, the daily amount of food consumed is allowed to be taken according to the table.

5.10 When determining the estimated consumption of water and wastewater for the buildings of workshops and administrative and amenity buildings (ABA), in the absence of other data, it is allowed to assume that the total amount of water (excluding water consumption in showers) for household and drinking needs of workers is used in workshops and ABA equally .

5.11 When designing residential buildings with a set of sanitary appliances that differs significantly from that adopted in Table A.2 for standard projects houses with varying degrees of improvement, it is allowed to determine the estimated specific average daily water consumption for the year by summing up the costs for individual devices (Table A.1 Appendix A), taking into account their number and specific types provided for in the project.

5.12 When designing water pipelines for industrial or other enterprises that supply water simultaneously for domestic and drinking needs and for technological purposes, in cases where it is known that technological costs are not random variables, a simple summation of the calculated maximum hourly and second flow rates of cold and hot water is allowed , determined in accordance with Section 4, and the corresponding costs for technological purposes, determined by the design task.

If the design task establishes (allows) that the flow rates of cold and hot water for technological purposes are random variables, but all parameters of the distribution functions of these random variables are not set, then it is allowed in the calculations to replace the water flow rates with technological equipment by a conditional number of additional sanitary appliances.

At the same time, the additional number of sanitary appliances is determined as the quotient of dividing the average hourly consumption of water (cold, hot, general) for technological purposes (by all types of equipment) specified by the design task by the average hourly consumption of one of the known types of appliances (taken from Table A .1, STO 5.2-01, for example - for washing with a mixer in a residential building). Further calculations to determine the estimated water consumption are recommended to be carried out without dividing the costs for household and drinking needs and technological purposes.

5.13 In cases where the design assignment for a particular facility does not specify the number of consumers and, accordingly, the data in Table A.3 cannot be used to determine the estimated flow rates of water and wastewater, the indicated estimated costs are determined based on data on water consumption ( general, hot, cold) various types sanitary appliances (see Table A.1, STO 5.2-01), taking into account the purpose (type) of the facility where these appliances are installed.

In this case, the average estimated specific hourly water consumption

^hr ud" q hr d ’ q hr d^"

estimated average hourly consumption in total by all types of sanitary appliances in the estimated section of the water supply network for the total number of appliances.

5.14 For buildings in which a combined system of domestic drinking and fire-fighting water supply is provided, the calculated maximum second flow rates of water (general and cold), determined in accordance with 4.4, must be increased by the value of the calculated maximum second flow rate of water for fire extinguishing needs, determined in accordance with with the data of tables 3, 4, 5 of section 7 of STO 5.2-01.

carpet for a residential building

6.1.1 Initial data.

For the calculation, a 16-storey apartment building located in the 1st building-climatic region was adopted; (4 sections; N = 256 apartments; 3 people in an apartment; U = 768 people (256 * 3); 16 sewer risers. The house is landscaped with cold and hot water supply systems and a fire-fighting water supply system.

The house is equipped with sanitary appliances:

Kitchen sink;

Bathtub 1500 mm long;

Wash basin;

Toilet bowl with a flush tank with a capacity of 6,5 l.

Each apartment has four water points in the cold water supply system (256*4=1024) and three points in the hot water supply system (256*3=768).

6.1.2 It is required to determine:

All types of estimated water costs for the house as a whole;

Estimated costs of wastewater for one sewer riser;

Estimated costs of drains for the house as a whole (outlet length 1_= 100 m);

Estimated costs of drains for a sectional outlet (L = 15 m), combining 4 risers in one section of the house.

1. INTRODUCTION

"Manual for determining the estimated costs of water and wastewater in water supply and sewerage systems of buildings and microdistricts" (hereinafter referred to as the Manual) was developed to help specialists of organizations designing water supply and sewerage systems for buildings and microdistricts of urban and rural development, including the initial sections of the sewer network from plastic pipes diameter up to 200 mm. Estimated water flow rates in the drainage systems of buildings and structures are not considered in this Handbook.

This Handbook provides a brief description of various mathematical models of water consumption - distribution functions of the probability of occurrence of expenses of various sizes and durations (hourly, short-term). These models can and should be used to predict the expected costs of water and wastewater, which are required for use in design practice when determining (in calculating) certain parameters of the elements of water supply and sewerage systems of buildings and microdistricts - such costs are commonly called "estimated costs".

The procedure for determining the estimated water consumption (section 4 of the Handbook) was adopted according to STO 02494733 5.2-01-2006 “Internal water supply and sewerage of buildings” (JSC “SantekhNIIproekt”), and links are also given to the tables of Appendix A of the specified standard.

The values of estimated costs in cold and hot water supply systems, determined in accordance with this Manual, differ slightly from the values of water costs, determined in accordance with SNiP 2.04.01-85 "Internal water supply and sewerage of buildings".

At the same time, the use of STO 5.2-01 and this Manual allows specialists of design organizations to determine those values of water and wastewater flow rates, the determination of which was not previously regulated.

6.1.4 We determine the estimated average daily water consumption (m 1 / day) in general for apartment building in accordance with 4.2 and summarized in table 6.1.2.

Table 6.1.2

Indicators	Formula for calculation
Estimated average daily water consumption (total), Qtf?		192 m/day
Estimated average daily consumption of hot water, Q^		115-768 00 „ 3 . 88.3 m/day
Estimated average daily consumption of cold water, Qj.		135 - 768 \u003d 103.7 3 / day 1000
Note-In accordance with the note to clause 4.2 with homogeneous (identical) consumers in formulas (1-3, clause 4.2), the summation of the daily water consumption of consumers is replaced by multiplying the average daily water consumption (l / day) by the number of consumers.

6.1.5 Determine the estimated average hourly water consumption

elk - minimum hourly water flow rates (should be used when selecting the diameters of water meters), short-term flow rates of wastewater in sewerage systems (water flow rates of various durations should be used when determining the diameters of risers and horizontal sections of sewerage networks).

conditional

counter,

Water consumption, m 3 / h

Threshold

vitality

Maximum

water volume

hydraulic

resistance

counter

At present, after many years of research, it is generally recognized that the processes of water consumption, as well as the processes derived from them - the processes of water disposal, are random and to describe them (to build mathematical models of such processes), methods of probability theory, mathematical statistics and the theory of random processes should be used. .

Obviously, at any given time, the total flow of water and wastewater at an object (residential building, utility or industrial enterprise, any group of different objects) is the sum of random flows through various sanitary appliances. When creating methods for mathematical modeling of water consumption (water disposal) processes, only those factors, the values of which are most significant and known during design, are always chosen as influencing water (runoff) costs.

For the practical application of various methods, the estimated water flow rates are presented in the form of tables of flow rates or tables of some auxiliary values, which make it quite easy to determine the flow rates for various combinations of initial data. Effluent flow rates are determined depending on the estimated water flow rate for a particular section of the network (respectively, on the number of sanitary appliances connected to the section) or the designed facility as a whole.

Back in the 30s of the XX century, S.A. Kursin proposed to replace the entire variety of water-folding devices at the facility with one equivalent device. The number of such equivalent devices is assumed to be equal to the total number of real devices, and the operating mode is assumed to be quite simple - the device is either switched on with constant expense, or you- 2

keys (this mode, of course, is quite different from the real one). The total turn-on time of an equivalent device (t B) during a period (T) determines the probability of this device being active for a given period of time (P). P \u003d t B / T.

Water flow rates, which are determined during design, are only a forecast of individual values (from general series predicted costs described by one or another probability distribution function) necessary to determine (calculate) certain parameters of the elements of water supply and sewerage systems: pipeline diameters, volumes of containers, types and brands pumping units, diameters of water meters, etc. That is why the term "estimated costs" is adopted in design practice. When comparing different methods for determining the estimated water flow, it is not enough to compare only individual values estimated costs (they may vary, sometimes significantly), but the validity and results of calculating the parameters of the elements of water supply and sewerage systems should be compared.

Based on the hypothesis of S.A. Kursin about an equivalent device (a similar hypothesis was proposed in 1940 and by Hunter in the USA), the estimated water consumption for a set of identical equivalent devices can be determined from a very simple formula q-q 0'm,

where m is the number of simultaneously switched on equivalent devices from their total number in the water supply system; q 0 - the consumption of an equivalent device accepted for this system.

In the works of S.A. Kursin and Hunter, these values were determined on the basis of logical reasoning about the operating modes of systems internal water supply buildings (mainly residential buildings), which, of course, could not provide high reliability of calculations when large residential areas appeared in the 50s, where water supply systems were already served big number heterogeneous consumers and a variety of sanitary appliances.

To improve the reliability of calculations for formula in the 60s of the XX century L.A. Shopensky carried out a set of studies, the main purpose of which was to develop new approaches to

determination of q 0 and P values for various combinations of initial data -

the number and purpose of sanitary appliances, various purposes of water supply facilities, various pressures water in pipelines of water supply systems, etc. At the same time, the main hypothesis of S.A. Kursin and Hunter on the existence of an equivalent L.A. Shopensky was not in doubt, and the calculation of the estimated flow rate was also carried out. That is why the method for determining the estimated costs based on this formula is hereinafter referred to as the Kursin-Hunter-Chopensky method (KHSh method).

Since 1976, the KHSH technique has been included in SNiP 11-30-76 "Internal water supply and sewerage of buildings", while general ideas about the possibility of calculations based on the parameters of an equivalent device were extended to the case of determining the estimated (maximum) hourly water consumption.

AT building codes and the rules approved in 1985, the KHSH methodology was also included with some simplifications introduced to facilitate its use in the practice of design organizations.

The data in tables of appendices 2 and 3 of SNiP 2.04.01-85 should be considered as very approximate conditional values of the required initial data. There are no data for experimental determination of these values, and there is no acceptable method for obtaining them on the basis of measured water consumption at various objects.

In the works of A.Ya. Dobromyslov showed that the idea of an equivalent device, as well as the idea of determining the number of simultaneously operating devices, cannot be used as a basis for calculating the estimated flow rates in building sewerage systems. Here, in addition to the simultaneity of turning on water-folding devices, it should also be taken into account that the working devices are connected in various places sewerage system, and in the section for which the pipeline diameter is determined, it is necessary to take into account differences in the time of movement (running) of water from individual devices to a given section of the system.

3 STATISTICAL METHODOLOGY FOR DETERMINING THE ESTIMATED WATER COSTS

The noted shortcomings of the KHSH method were a prerequisite for carrying out theoretical work on the creation of another method for determining the estimated water flow rates at the MosvodokanalNIIproekt Institute (A.S. Verbitsky, A.L. Lyakmund). The idea behind the methodology of the MosvodokanalNIIproekt institute (hereinafter referred to as the MVKNIIP methodology) is that the change in time of water consumption measured at any facility should be considered as an implementation of a random process of water analysis by consumers, formed from a variety of inclusions of various devices with random values of water consumption through each of them. . At the same time, no assumptions are made about the probabilities of switching on certain sanitary appliances, about the duration of switching on, about the functions of distributing water consumption for each of the devices. Observed (measured) water discharges are processed by standard methods of mathematical statistics and the theory of random processes.

The total random process of water withdrawal for one day (with water consumption equal to the average daily for the year), in accordance with the theory of random processes, can be represented as a simple sum of two processes - regular and random. For the first of them (regular), the main characteristics are the mathematical expectation and dispersion of hourly water flow rates. The estimate of this non-zero mathematical expectation is the annual average hourly water consumption at the facility. It is obvious that it is easily determined from the data of experimental measurements or is calculated as the product of the number of devices or consumers by the normative annual average specific hourly consumption for any composition of the device or consumers. The regular component of the total random process of water withdrawal is a simple graph of the average water flow for each hour of the day, for which the dispersion of the values of the average hourly water flow for each hour of the day is also easily calculated.

The values of the random component of the total process are easily found if from each value of the hourly water consumption at any hour

days, subtract the value of the average water consumption for a given hour of the day. The mathematical expectation of the random component of the total water withdrawal process turns out to be equal to zero, and the dispersion of this process is easily determined from experimental data and is denoted by D r hr (r - from the word random - random).

If, according to the data on dispersions and mathematical expectations of the indicated components (regular and random) of the total random process of water withdrawal, we find the distribution function of random values of hourly water flow rates, then from this distribution it will not be difficult to find those values of hourly flow rates that will meet the requirements of one or another calculation of system parameters water supply or sewerage. To do this, it is necessary to additionally set only the value of the provision of the desired water flow - G (the value of t in this case is equal to 1 hour, and T = 8760 hours, i.e. 1 year). In the MVKNIIP method, the value of G is assumed to be 0.9997, i.e. the calculated maximum hourly water flow can only be exceeded for approximately 3 hours per year (0.0003 8760).

For calculations of water supply and sewerage systems, in addition to the maximum hourly costs, costs with a different duration t may be required. At the same time, the processing of experimental data and the theoretical analysis of the water withdrawal process

show that the distribution function can be constructed for expenses of any duration, and the parameter of such a function is the dispersion D r ,. which can be determined depending on the values of t and Dl. If the variance m is found, then the estimated water flow can also be determined from a series of random flows with duration t (for this, as before, it is required to set the values of T and Gj.B to the MVKNIIP method ( in the tables of estimated costs) it is assumed that G = 0.9997 for short-term costs with t = 2 minutes during the hour of maximum drawdown. This means that the excess of the calculated costs is possible for 6-7 minutes during the hour of maximum drawdown (this is the hour for which the largest average value of water consumption is determined in the regular component of the process).

the dimension of short-term flows is defined as l / s, although in fact, flows with a duration of t = 2 min are considered. It should be noted that even S.A. Kursin noted the difference between the dimension of expenditures and their duration. Such differences are inevitable, in particular, because the registration of water discharges with a duration of 1s is practically impossible under the existing measuring instruments(because of their inertia). In the KHS method, such differences are also present, but in a hidden form.

The way to obtain the necessary dependences of the change in the parameters of the distribution functions of water discharges of various durations (mathematical expectations of the variances of the components of a random process of water withdrawal) is methodically simple and understandable - this is a standard statistical analysis of measurement data with registration of the values of influencing factors, identifying, if necessary, the dependences of the parameters of distribution functions on each from the factors. At the same time, it should be borne in mind that the total influence of all factors that were not previously taken into account in the MVKNIIP methodology is no more than 10–15%, that is, no more than 10–15% of the total dispersion of random values of measured water flow rates remained regardless of the values taken into account in factor models (N, Q average) This way is really feasible, which basically distinguishes the MVKNIIP method from the KKhS method.

Currently, in buildings for various purposes, in apartments of residential buildings, a large number of cold and hot water meters are installed. These meters often have electric impulse sensors, the frequency of which is proportional to water flow, and there are also a large number of special data recorders that make it very easy to collect and process actual data on water consumption at various facilities using the MVKNIIP method on a computer.

The new method for determining the estimated flow rates of effluents is based on the results of studies of the patterns of formation of short-term flow rates of effluents in the pipelines of sewerage systems of buildings, conducted by A.Ya. Dobromyslov in the 60s - 80s of the XX century. As a result of these works, it was found that short-term wastewater discharges are a function not only of water discharges through sanitary

technical devices that are connected to the relevant section of the sewer network, but also the layout of this network, its capacity. The main difference between the conditions for the formation of wastewater flows is that in this case the condition of continuity of the flow, which operates in water supply networks, is not observed. For example, with the simultaneous discharge of wastewater from several devices located in different sections of the same building into one outlet pipeline, these costs may never occur in the calculated network section. At the same time, the longer the outlet pipeline (i.e., the farther from one another the devices are located), the less likely it is that these costs will overlap.

Works by A.Ya. Dobromyslova showed that approaches to determining the estimated flow rates for risers and for branch (horizontal) sections of the network should be different. In the hydraulic calculation of risers, the calculation criterion is to prevent the failure of the hydraulic seal in any of the devices connected to the riser. Therefore, for such a case, it is necessary to summarize the calculated second flow rate of water and the second flow rate of the effluents of the device with the maximum drainage, as a rule, of the toilet flush tank.

When calculating horizontal pipelines, which usually do not work with a full cross section (in this case, there is no danger of a breakdown of hydraulic seals), water discharges with the longest duration should be taken as calculated ones - these are obviously the costs from devices with the largest capacity (bath with a volume of 140-180 l , emptying time 160-180 s).

The above description of the main principles of the two different methods for determining the estimated flow rates of water and effluents is short and simplified. For a deep understanding of the specifics, advantages and inevitable disadvantages of each of them, for the development of new methods or the improvement of existing ones, a deep study is required. theoretical foundations these methods.

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