Hydraulic calculation of the heating system. Download Methodological manual
1 area of \u200b\u200buse
2. Regulatory references
3. Basic terms and definitions
4. General provisions
5. Qualitative characteristic of surface runoff from residential areas and enterprises
5.1. Choosing priority indicators of pollution of surface runoff in the design of wastewater treatment plants
5.2. Determination of the estimated concentrations of pollutants when the surface flow for cleaning and released into water bodies
6. Systems and structures of surface runoff displacement with residential areas and enterprises sites
6.1. Systems and schemes for surface sewage
6.2. Determination of the estimated costs of rain, melting and drainage waters in rain sewer collectors
6.3. Determination of the estimated wastewater costs of the sedipant sewage system
6.4. Regulation of wastewater costs in the rain sewage network
6.5. Pumping Surface Stream
7. Calculated surfaces of surface wastewater from residential areas and fields of enterprises
7.1. Determination of average annual volumes of surface wastewater
7.2. Determination of the calculated volumes of rain wastewater assigned to cleaning
7.3. Determination of the estimated daily volumes of melt waters allowed for cleaning
8. Determination of the estimated productivity of surface drain wastewatering structures
8.1. Current productivity of accumulative treatment facilities
8.2. Calculation productivity of flow-up treatment facilities
9. Terms of surface runoff with residential areas and enterprises sites
9.1. General provisions
9.2. Determination of standards for permissible discharge (VAT) of substances and microorganisms when producing surface wastewater into water bodies
10. Claiming surface runoff
10.1. General provisions
10.2. Selection of type of treatment facilities on the principle of water flow control
10.3. Basic technological principles
10.4. Cleaning the surface runoff from large mechanical impurities and trash
10.5. Separation and regulation of runoff on sewage treatment plants
10.6. Cleaning the drain from heavy mineral impurities (sandowing)
10.7. Battery and preliminary lightening of drain by static settling
10.8. Reagent surface flow treatment
10.9. Cleaning surface runoff with reagent settling
10.10. Cleaning surface drain reagent flotation
10.11. Cleaning surface drain by contact filtering method
10.12. Superficial UK filtration
10.13. Adsorption
10.14. Biological cleaning
10.15. Ozonization
10.16. Ion exchange
10.17. Barbecue processes
10.18. Disinfection of surface drain
10.19. Handling of technological processes for cleaning surface sewage
10.20. Basic requirements for monitoring and automating technological processes of cleaning surface wastewater
Bibliography
Appendix A. Terms and Definitions
Appendix B. The value of rain intensity values
Appendix B. Values \u200b\u200bof parameters to determine the calculated expenses in rain sewer collectors
Appendix G. Map of Zoning the territory of the Russian Federation on the layer of Melk
Appendix D. Map of Zoning the territory of the Russian Federation by the coefficient with
E. Appendix E. Methodology for calculating the volume of the tank to regulate the surface runoff in the rain sewage network
Appendix J. Methodology for calculating pumping stations for pumping surface drain
Appendix I. Methods for determining the value of the maximum daily layer of rain ducts for residential territories and enterprises of the first group
Appendix K. Methods for calculating the maximum daily layer of precipitation with a given probability of exceeding
Appendix L. Normated deviations from the average value of the ordinate logarithmically normal distribution curve F with different values \u200b\u200bof the security and asymmetry coefficient
Appendix M. Normated deviations of the ordinate binominal distribution curve F with different values \u200b\u200bof the security and asymmetry coefficient
Appendix N. The average daily layers of precipitation of the NWR, coefficients of variation and asymmetry for various territorial areas of the Russian Federation
Appendix P. Methodology and an example of calculating the daily volume of melt waters assigned to cleaning
V. V. Pobotilov
V. V. Pobotilov
by calculating heating systems
V. V. Pobotilov
By calculating heating systems
Candidate of Technical Sciences, Associate Professor V. V. Pogotylov
Allowance for calculating heating systems
Allowance for calculating heating systems
V. V. Pobotilov
Vienna: company "Herz Armaturen", 2006
© Firm "Herz Armaturen", Vienna, 2006
Preface |
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2.1. Choose and placement of heating devices and elements of the heating system |
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in the premises of the building |
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2.2. Device to regulate the heat transfer of the heating device. |
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Methods of attachments of various types of heating devices to |
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heating system pipelines |
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2.3. Selection of the water heating system to the thermal networks |
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2.4. Designing and some provisions for the performance of drawings |
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heating systems |
3. Determination of the calculated heat load and the coolant consumption for the settlement section of the heating system. Determination of calculated power
water heating systems |
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4. Hydraulic calculation of water heating system |
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4.1. Initial data |
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4.2. Basic principles of hydraulic calculation of the heating system |
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4.3. Sequence of hydraulic calculation of the heating system and |
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selection of regulating and balance valves |
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4.4. Features of the hydraulic calculation of horizontal heating systems |
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with hidden gasket pipelines |
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5. Designing and selection of thermal item equipment |
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water heating |
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5.1. Selection of water heating circulation pump |
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5.2. Select the type and selection of the expansion tank |
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6. Examples of hydraulic calculation of two-pipe heating systems |
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6.1. Examples of hydraulic calculation of the vertical two-pipe system |
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heating with upper wiring of trunk thermal pipelines |
6.1.1.
6.1.3. An example of hydraulic calculation of the vertical two-pipe system
heating with upper wiring using radiator valves
6.2. An example of hydraulic calculation of the vertical two-pipe system
heating with lower wiring using the Herz-TS-90 valves and
Hertz-RL-5 for radiators and pressure regulators of hertz 4007
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V. V. Pogotylov: allowance for the calculation of heating systems
6.3.
6.5. Example of hydraulic calculation of the horizontal two-pipe system
heating using a single-point radiator valve
7.2. Example of hydraulic calculation of the horizontal single-tube system
heating with the use of radiator nodes of Hertz-2000 and regulators
7.5. Examples of valve applicationsHertz-TS-90-E Hertz-Ts-E when designing
heating systems and during the reconstruction of existing
8. Examples of the use of three-way valves hertz art.no7762
from thermomotors and servo drives of the hertz when constructing systems
heating and cold supply |
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9. Designing and calculation of floor heating systems |
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9.1. Designing outdoor heating systems |
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9.2. Basic principles and sequence of thermal and hydraulic |
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calculation of outdoor heating systems |
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9.3. Examples of thermal and hydraulic calculation of outdoor heating systems |
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10.Plovaya calculation of water heating systems |
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Literature |
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Applications |
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Appendix A: Nomogram of hydraulic calculation of water pipelines |
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heating from steel pipes at k sh \u003d 0.2 mm |
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Appendix B: nomogram of hydraulic calculation of water pipelines |
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heating from metal-polymer pipes at k sh \u003d 0.007 mm |
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Appendix B: local resistivity coefficients |
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Appendix M: Pressure Losses on Local Resistance Z, Pa, |
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depending on the sum of the coefficients of local resistance σζ |
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Appendix D: Nomogram D1, D2, D3, D4 to determine the specific |
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heat transfer Q, W / m2 floor heating systems depending |
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from the average temperature difference Δt cf |
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Appendix E: Thermal Characteristics of the Panel Radiator Vonova |
Page 4.
V. V. Pogotylov: allowance for the calculation of heating systems
Preface
When creating modern buildings of various purposes, the developed heating systems should have appropriate qualities designed to provide thermal comfort or the required thermal conditions in the premises of these buildings. The modern heating system must correspond to the interior of the premises, be convenient in operation and
still for users. Modern heating system allows automatic mode
redistribute heat flows between the premises of the building, to the maximum degree of
you can use regular and irregular internal and external heat absorbents that are not included in the heated room must be programmable for any thermal regimes.
predation of premises and buildings.
To create such modern heating systems, a significant technical diversity of shut-off and regulating reinforcement is required, a certain set of regulatory instruments and devices, a compact and reliable structure of the pipeline kit. The degree of reliability of each element and device of the heating system should meet modern high requirements and be identical between all the elements of the system.
The present allowance for the calculation of water heating systems was built on the integrated use of equipment of the company Hertz Armaturen GmbH for buildings of various purposes. This manual is developed in accordance with current standards and contains the main reference
and technical materials on the text and in applications. When designing additionally, the company's catalogs, construction and sanitary standards should be used, a special right
surplus literature. The book is focused on specialists who have the education and practice of designing buildings.
In the ten sections of this manual, guidelines and examples of hydraulic
and thermal calculation of vertical and horizontal water heating systems with
measures of the selection of thermal items.
In the first section, the reinforcement of the company HERTS ARMATUREN GMBH, which is conditionally divided into 4 groups. In accordance with the systematization presented developed
methods of design and hydraulic calculation of heating systems that are outlined in
sections 2, 3 and 4 of this manual. In particular, the principles of the selection of reinforcements of the second and third group are methodologically different, the main provisions for the selection are identified.
pressure drop regulators. In order to systematize the method of hydraulic calculation
various heating systems in the manual are introduced by the concepts of "adjustable section" circulating
ring, as well as the "first and second direction of hydraulic calculation"
By analogy with the type of the nomogram of the hydraulic calculation for metal-polymer pipes, a nomogram of hydraulic calculation of steel pipes is composed into the manual, widely used for open gasket of trunk thermal pipelines and for strapping equipment of thermal items. In order to increase the informativeness and reduction of the allowance for the nomogram of the hydraulic selection of valves (Normal), supplemented with the information of the total valve type and the technical characteristics of the valve, which are placed on the free part of the field
In the fifth section, the method of selecting the main type of equipment for thermal
nodes that are used in subsequent sections and in the examples of hydraulic and thermal
calculations of heating systems
In the sixth, seventh and eighth sections, examples are given examples of the calculation of various two-pipe and single-tube heating systems in aggregate with various versions of heat sources
- flue or thermal networks. Examples also provide practical recommendations for the selection of pressure drop regulators, according to the selection of three-way mixing valves, according to the selection of expansion tanks, on the design of hydraulic separators, etc.
outdoor heating
In the tenth section, the method of thermal calculation of water heating systems is given and
meeting of various heating devices for vertical and horizontal two-pipe and single-tube heating systems.
Page 5.
V. V. Pogotylov: allowance for the calculation of heating systems
1. General technical information about the products of the company HERTS ARMATUREN GMBH
The company HERTS ARMATUREN GMBH produces a full range of equipment for water
heating and cold supply: regulating valves and shock fittings, electronic control regulators and direct-acting regulators, pipelines and connecting fittings, water boilers and other equipment.
Hertz produces regulating valves for radiators and for thermal items with
the variety of sizes and executive mechanisms to them. For example, for radiator
valves produced the widest range of interchangeable executive
hanisms and thermostators - from a variety of design and appointment of thermostatic
direct heads to electronic programmable PID regulators.
The method of hydraulic calculation set forth in the manual is modified depending on
species of valves used, from their structural and hydraulic characteristics. We divided the reinforcement of Hertz into the following groups:
Shock fittings.
A group of universal fittings that does not have hydraulic setting.
A group of fittings, which has a device for configuring hydraulic co-
contacts for the desired value.
To the first group of reinforcement, operated in the provisions of the full opening or complete
closing related
- valve valvesStremexx-D, Stremex-A, Stremex-AD, Strolrex-G,
Strolrex-Ag,
Gutz gutz
- valves stop for radiatorHertz-RL-1-E, Hertz-RL-1,
- ball, cork taps and other similar fittings.
To the second grouparmatures that do not have hydraulic settings can be attributed:
- thermostatic valvesHertz-TS-90, Hertz-TS-90-E, Hertz-Ts-E,
Hertz-Vua-T, Hertz-4WA-T35,
- connection nodesHertz-3000,
- connection nodesHertz-2000 for single-tube systems,
- single-point connections to the radiatorHertz-VTA-40, Hertz-VTA-40-Uni,
Hertz-Vua-40,
- three-way thermostatic valvesCalis-TS,
- valves Three-way regulating hertz art.no 4037,
- distributors for connecting radiators
- another similar fittings in a constantly updated assortment of produced products of the company HERTS ARMATUREN GMBH.
To the third group of reinforcement having hydraulic setting to install the required
about hydraulic resistance can be attributed
- thermostatic valvesHertz-TS-90-V, Hertz-TS-98-V, Hertz-TS-FV,
- balance valves for radiatorHertz-RL-5,
- radiator hand valvesHertz-AS-T-90, Hertz-As, Hertz-GP,
- connection nodesHertz-2000 for two-pipe systems,
- balance valvesSteterxx-GM, Stremex-M, Stremex-GMF,
Steterxx-MFS, Stremex-Gr, Stremex-R,
- automatic pressure regulator HERTS ART.NO 4007,
Hertz art.no 48-5210 ... 48-5214,
- automatic flow regulator Hertz Art.no 4001,
- shipping valve for maintaining the pressure drop of hertz art.no 4004,
- distributors for outdoor heating
- other fittings in a constantly updated assortment of products
firms of Hertz Armaturen Gmbh.
The valves of the Herz-TS-90-KV series, which in their own, should be attributed to a special group of reinforcement.
constructions relate to the second group, but are selected according to the method of calculating valve valves
group.
Page 6.
V. V. Pogotylov: allowance for the calculation of heating systems
2. Selection and design of heating system
Heating systems, as well as the type of heating devices, the view and parameters of the coolant
nights in accordance with the construction norms and design task
When designing heating, it is necessary to provide automatic regulation and instruments for taking into account the number of heat consumed, as well as apply energy-efficient solutions and equipment.
2.1. Selection and placement of heating devices and system elements
heating in the premises of the building
Design of heating
lags a comprehensive solution to the following
1) individual choice of optimal
variant of the type of heating and the type of heating
instrument providing comfortable
conditions for each room or zone
premises
2) definition of location
the valid devices and their required size to ensure the conditions of comfort;
3) individual choice for each heating device of the type of regulation
and sensor locations depending
from the appointment of the room and its thermal
inertia, from the size of possible
external and internal thermal perturbations
from the type of heating device and from it
thermal inertia, etc., for example,
two-position, proportional,
ramated regulation, etc.
4) the choice of the type of connection of the heating device to the heat pipelines of the system
5) solving pipeline placement scheme, the choice of type of pipes, depending on the required value, aesthetic and consumer qualities;
6) selection of system connection scheme
heating to thermal networks. With designer
the corresponding heat is performed
you and hydraulic calculations allow
to choose materials and equipment
heating and thermal item
Optimal comfortable conditions
it is applied to the right choice of the type of heating and the type of heating device. Heating devices should be placed, as a rule, under light openings, providing
access for inspection, repair and cleaning (Fig.
2.1A). As heating devices
convectors. Place the heating
rooms rooms (if there is indoors
two or more outer walls) with the aim of liquid
dating downwards on cold flood floor
air. Due to the same circumstances. Length
the heating device should be
not less than 0.9-0.7 width of window openings
heated premises (Fig. 2.1a). Floor-
the height of the heating device must be less than the distance from clean floor to
the bottom of the windows (or the bottom of the window opening during its absence) is not valid
less than 110 mm.
For premises whose floors are made of materials with high thermal active
(ceramic tile, natural
stone, etc.) appropriate on the background of
pretended heating with the help of heating
appliances create a sanitary effect with
using outdoor heating
In the premises of various purposes
with a height of more than 5 m in the presence of vertical
light opening should be under them
place the heating devices to protect working from cold descending
air flows. At the same time such
the solution creates directly from the floor
increased coolest speed
spongy along the floor of the air flow, speed
which often exceeds 0.2 ... 0.4 m / s
(Fig. 2.1b). With an increase in the power of the device, uncomfortable phenomena are enhanced.
In addition, due to an increase in air temperature in the upper zone, significantly
toleut the heat loss room
In such cases, to ensure thermal comfort in the working area and reduce
pollen heating or radiant heating
with radiation heating
instruments disposed in the upper zone at a height of 2.5 ... 3.5 m (Fig. 2.1b). Additional
it follows light openings
place heating devices with heat
howl load on the reimbursement of the heat loss of this light opening. In the presence of B.
such premises of permanent jobs
in the areas of jobs to ensure thermal comfort in them using either
air heating systems, or using local radiation devices over workplaces, or using
this is under light openings (windows) for
estimated thermal load of the device
protection of working from cold descending
blowing to make equal to the calculated thermal
air flows should be placed
losses of this upper luminous opening
heating devices with thermal load on
with a reserve of 10-20%. Otherwise
reimbursement of the heat loss of this light
the surface of the glazing will occur
satoomation.
Fig. 2.1.: Examples of placement of heating devices in rooms
a) in residential and administrative premises with a height of up to 4 m;
b) indoors of various purposes with a height of more than 5 m;
c) indoors with upper lights.
In one system of heating is allowed
the use of heating devices
personal types
Built-in heating elements are not allowed to be placed in single-layer
exterior or interior walls, as well as in
partitions, except for the heater
elements built into internal
walls and partitions chambers, operating
and other premises of therapeutic treatment of hospitals.
It is allowed to provide in multilayer outdoor walls, overlaps and
floors heating elements of water
heating, deposited in concrete.
In the staircases of buildings up to 12
just the heating devices are allowed
to place only on the first floor at the level
entrance doors; Installation of heating
devices and heat lines of heat lines in the volume of the tambour is not allowed.
In the buildings of medical institutions Heating devices on staircases
Page 8.
V. V. Pogotylov: allowance for the calculation of heating systems
Heating devices should not be placed in tambour compartments having
rubber doors
Heating devices on the staircase
the cell should be attached to a separate
branches or risers of heating systems
Heating system pipelines follows
design from steel (except oct
bathrooms), copper, brass pipes, as well
heat-resistant metal-polymer and poly-
measuring pipes.
Pipes made of polymeric materials
loaded hidden: in the structure of the floor,
behind the screens, in stranges, mines and canals. Open gasket of these pipelines
it is allowed only within the fire sections of the building in places where their mechanical damage is excluded, external
greighs of the outer surface of pipes more than 90 ° C
and direct impact of ultraviolet
rights. Complete with polymer pipes
materials should be applied to
bulk parts and products corresponding to
applied pipe type.
The biases of pipelines should be taken
mother is at least 0.002. Gasket is allowed
pipes without slope at the speed of water movement in them 0.25 m / s or more.
Shut-off valves should be provided
tRIVE: To disable and descend water from
separate rings, branches and risers of systems
heating, for automatically or distant
controlled valves; To disable
part or all heating devices in
premises in which heating is used
it is periodically or partially. Shut-off
armature should be provided to
cera to attach hoses
In the pumping systems of water heating
should be provided, as a rule,
accurate air collectors, cranes or automatic
ticker. Non-flow
the air collectors are allowed to provide for water speed in the pipe
wire less than 0.1 m / s. Using
immediate fluid desirable
use to remove the air automatic
ticker Air Sweets - Separators,
installed, as a rule in thermal
point "to the pump"
In heating systems with lower layout of highways to remove air
separate installation of airports
cranes on the heating devices of the upper
floors (in horizontal systems - to each
house heating device).
When designing systems of Central
water heating from polymer pipes should include automatic devices
regulation (limiter
perats) to protect pipelines
from exceeding the parameters of the coolant
Each floor has built-in mounting cabinets, in which there must be
disseminating dispensers
pipelines, shut-off valves, filters, balance valves, as well as counters
meeting heat
Pipes between distributors and heating devices are laid
outdoor walls in a special protective
corrugated pipe or thermal insulation, in
floor structures or in special plinth
sah-konta
2.2. Devices for regulating the heat transfer of the heating device. Methods of connections of various types of heating devices to the pipelines of the heating system
To regulate air temperature
in the premises of heating devices
blows adjusting fittings
Indoors with permanent residences
people are usually installed
automatic thermostators
maintenance of the predetermined temperature
ry in each room and supply savings
heat due to the use of internal
insolers (domestic heat dissipation,
solar radiation).
Not less than 50% of heating
borov installed in one room
funds should be installed regulating
reinforcement, with the exception of instruments in
where there is a danger of freezing
heat carrier
In fig. 2.2 shows various options
you are temperature regulators that can
be installed on thermostatic
diastrian valve.
In fig. 2.3 and fig. 2.4 show options
the most common connections of various types of heating devices to two-pipe and one-tube systems
Regulatory documents are given, regulating the design of the design systems for the leading and purification of surface (raindrop, melting, polyvochetic) wastewater from residential areas and platforms of enterprises, as well as comments on the provisions of the joint venture 32.13330.2012 "Sewerage. External networks and structures "and" Recommendations for the calculation of systems for collecting, leading and cleaning a surface runoff from residential areas and sites of enterprises and determining the conditions for the release of it into water bodies "(OJSC NII Vodgeo). The specified documents allow for a discharge to clean the most contaminated part of the surface runoff in the amount of at least 70% of the annual flow rate for residential territories and sites close to them for pollution, and all the volume of flow from the fields of enterprises whose territory can be contaminated with specific substances with toxic properties or significant content of organic substances. The generally accepted practice of designing engineering structures of separate and wide sewage systems, allowing short-term discharge of parts of the drain when intensive (storm) rare repeatability rains through separation chambers (livnesbrosis) into a water facility. Situations related to the failures of the territorial departments of state examination and Rosrybolov are considered in coordinating the implementation of activities on the projected capital construction objects on the basis of Article 60 of the Water Code of the Russian Federation prohibiting the wastewater and neutralization and neutralization.
Keywords
List of cited literature
- Danilov O. L., Kostyuchenko P. A. Practical manual for the choice and development of energy-saving projects. - M., ZAO TEKHNOPROMSTROY, 2006. P. 407-420.
- Recommendations for calculating systems for collecting, leading and cleaning the surface runoff from residential areas, enterprises sites and determining the conditions for the release of it into water bodies. Supplement to SP 32.13330.2012 "Sewerage. External networks and facilities "(updated edition SNiP 2.04.03-85). - M., OJSC NII Vodgeo, 2014. 89 p.
- Vereshchagin L. M., Menshutin Yu. A., Shvetsov V.N. On the regulatory framework for the design of the system of leading and purification of surface wastewater: IX Scientific and Technical Conference "Yakovlevsky Readings". - M., MGSU, 2014. P. 166-170.
- Molokov M. V., Shifrin V. N. Cleaning the surface runoff from the territories of cities and industrial sites. - M.: Stroyzdat, 1977. 104 p.
- Alekseev M. I., Kurganov A. M. Organization of the leading of the surface (rain and thaela) runoff with urbanized territories. - M.: Publishing House of the DC; St. Petersburg, SPbgas, 2000. 352 p.
After collecting the source data, the determination of thermal loss of the house and the power of the radiators remains the hydraulic calculation of the heating system. Properly performed, it is a guarantee of correct, silent, stable and reliable operation of the heating system. Moreover, it is a way to avoid extra investment and energy costs.
Calculations and work that you need to perform in advance
Hydraulic calculation is the most time consuming and complex design.
- First, the balance of heated rooms and premises is determined.
- Secondly, it is necessary to choose the type of heat exchangers or heating devices, as well as perform their placement on the plan of the house.
- Thirdly, the calculation of the heating of a private house assumes that the choice is already made regarding the configuration of the system, types of pipelines and fittings (regulating and shut-off).
- Fourth, a drawing system should be made. It is best if it is aksonometric scheme. It should contain numbers, length of calculated sections and thermal loads.
- Fifth, the main circulation ring is installed. This is a closed loop, which includes serial sections of the pipeline directed to the instrument rink (when considering a single-tube system) or to the remote heating device itself (if a two-pipe system occurs) and back to the heat source.
The calculation of heating in a wooden house is performed by the same scheme as in a brick or in any other country cottage.
The procedure for conducting calculations
Hydraulic calculation of the heating system involves the solution of the following tasks:
- determining the diameters of the pipeline on different segments (however, economically appropriate and recommended coolant movement speeds are taken into account);
- calculation in different parts of hydraulic pressure losses;
- hydraulic linkage of all branches of the system (hydraulic instrument and other). It involves the use of regulatory reinforcement, which allows for dynamic balancing with non-stationary hydraulic and thermal modes of the functioning of the heating system;
- consumption of the coolant and calculation of pressure losses.
Are there free software for calculations?
To simplify the calculation of the private home heating system, you can use special programs. Of course, they are not as many graphic editors, but there is still a choice. Some are distributed free of charge, others in demo versions. In any case, make the necessary calculations one or twice will work without material investments.
Software "OVENTROP CO"
Free Software "OVENTROP CO" is intended to perform hydraulic calculation of the heating of a country house.
The OVENTROP CO program is designed to provide graphical assistance at the stage of the preparation of the heating project. It allows the hydraulic calculation for one-tube, and for a two-pipe system. It is easy to work in it and convenient: there are already ready-made blocks, controls errors, a huge catalog of materials
Based on preliminary settings and selection of heating devices, pipelines and reinforcements, you can design new systems. In addition, it is possible to adjust the existing scheme. It is carried out by selecting the capacity of the equipment already available in accordance with the needs of heated rooms and premises.
Both of these options can be combined in this program, allowing you to regulate existing fragments and design new ones. In any embodiment, "OVENTROP CO" selects the adjustment settings. In terms of the implementation of hydraulic calculations, this program has ample opportunities: from the selection of pipeline diameters before analyzing the water consumption in the equipment. All results (tables, diagrams, drawings) can be printed or transfer to Windows Wednesday.
INSTAL-THERM HCR Software
The "Instal-Therm HCR" program allows you to calculate the system of radiator and surface heating.
It comes with Instalsystem Tece, which includes three more programs: Instal-San T (for designing cold and hot water), Instal-Heat & Energy (for calculating heat loss) and Instal-Scan (for scanning drawings).
The "Instal-Therm HCR" program is equipped with advanced materials catalogs (pipes, water consumers, fittings, radiators, thermal insulation and locking fittings). The results of the calculations are issued as a specification for the materials and products offered by the program. The only lack of a trial version - it is impossible to withdraw it to print
Computational capabilities "Instal-therm HCR": - selection of pipe diameter and reinforcement, as well as tees, shaped products, distributors, passage couplings and thermal insulation of the pipeline; - determination of the height of the lifting of pumps located in the mixers of the system or on the plot; - hydraulic and thermal calculations of heating surfaces, automatic determination of the optimal input temperature (power); - Selection of radiators, taking into account the cooling in the pipelines of the working agent.
The trial version can be used for free, but it has a number of restrictions. First, as in most conditionally free programs, the results cannot be printed, as well as export them. Secondly, in each of the package applications, you can create only three projects. True, you can change them as much as you like. Thirdly, the created project is stored in a modified format. Files with such an extension none of the trial nor even the standard version will not read.
Software "Herz C.O."
The program "Herz C.O." is free. With it, it is possible to make hydraulic calculation and a single-pipe, and a two-pipe heating system. An important difference from others is the possibility of performing calculations in new or reconstructed buildings, where a glycolic mixture protrudes as a coolant. This software has a certificate of compliance of CMSPS LLC.
"HERZ C.O." Provides the user to the following options: the selection of pipes in diameter, settings of regulators of the pressure difference (branching, the base of the drain); analysis of water consumption and determination of pressure losses in equipment; Calculation of hydraulic resistance of circulating rings; accounting for the necessary prestiges of thermostatic valves; Reducing in circulation rings of overpressure by selecting the valve settings. For user convenience, a graphic data entry is organized. The results of the calculations are derived in the form of circuits and floor plans.
Schematic representation of the results of calculations in Herz C.O. It is much more convenient for the specification for materials and products, in the form of which are derived from the results of calculations in other programs.
The program has a developed contextual help providing information on individual commands or inserted indicators. Multi-digital mode of operation allows you to simultaneously view multiple data types and results. Working with a plotter and printer is very simply organized, you can preview the displayed pages before printing.
Program "Herz C.O." Equipped with a convenient feature of automatic search and diagnostics of errors in tables and in diagrams, as well as rapid access to catalog of reinforcement, heating devices and pipes
Modern control systems with a constantly changing thermal regime require equipment for monitoring changes and regulation.
Make a choice of regulatory reinforcement, do not own the situation on the market, it is very difficult. Therefore, in order to make the calculation of heating on the area of \u200b\u200bthe whole house, it is better to use the software application with a large library of materials and products. Not only the operation of the system itself, but also the amount of investment, which will be required for its organization depends on the correctness of the data obtained.
Today we will analyze how to produce the hydraulic calculation of the heating system. After all, to this day, the practice of designing heating systems for the Nativity is applied. This is fundamentally incorrect approach: without prior calculation, we will decide the plate of the material consideration, provoking abnormal modes of operation and make it possible to achieve maximum efficiency.
Objectives and objectives of hydraulic calculation
From a engineering point of view, the liquid heating system seems to be a rather complex complex that includes heat generation devices, its transportation and isolation in heated rooms. The ideal mode of operation of the hydraulic heating system is considered to be such in which the coolant absorbs the heat from the source and transmits it with a room atmosphere without losses during the movement process. Of course, such a task is visible completely unattainable, but a more thoughtful approach allows you to predict the behavior of the system in various conditions and as much as possible to the reference indicators. This is the main goal of designing heating systems, the most important part of which hydraulic calculation is considered to be.
The practical goals of hydraulic calculation are as follows:
- Understand how speed and in which the coolant is moving in each system node.
- Determine what impact has the change in the mode of operation of each of the devices to the entire complex as a whole.
- Set which performance and performance characteristics of individual nodes and devices will be sufficient to perform their functions with a heating system without significant rise in prices and ensure unreasonably high reliability stock.
- Ultimately - provide a strictly dosed distribution of thermal energy in various zones of heating and ensure that this distribution will be maintained with high constancy.
It can be said more: without at least the basic calculations it is impossible to achieve an acceptable stability of the work and durable use of equipment. Modeling the action of the hydraulic system, in fact, is a basis on which all further project development is built.
Types of heating systems
The tasks of engineering calculations of this kind are complicated by a high variety of heating systems, both in terms of scale and configuration plan. There are several types of heating junctions, each of which has its own patterns:
1. Two-pipe stubble systemsand the most common version of the device, well-suitable for organizing both central and individual heating circuits.
The transition from the heat engineering calculation to the hydraulic is carried out by the introduction of the concept of mass flow, that is, some mass of the coolant caused to each section of the heating circuit. The mass flow is the ratio of the required thermal power to the product of the specific heat capacity of the coolant to the temperature difference in the feed and return pipeline. Thus, on the sketch of the heating system, the key points for which the nominal mass flow is indicated. For convenience, in parallel, the volumetric flow is determined, taking into account the density of the coolant used.
G \u003d Q / (C (T 2 - T 1))
- Q - necessary thermal power, W
- c is a specific heat carrier heat, for water received 4200 J / (kg · ° C)
- Δt \u003d (T 2 - T 1) - temperature difference between feed and reverse, ° C
The logic here is simple: To deliver the required amount of heat to the radiator, you need to first determine the volume or mass of the coolant with a given heat capacity passing through the pipeline per unit of time. To do this, it is required to determine the speed of the coolant in the circuit, which is equal to the ratio of the volume flow to the cross-section of the internal passage of the pipe. If the rate calculation is maintained relative to the mass flow, the denominator must add the density value of the coolant:
V \u003d g / (ρ · f)
- V - the speed of the coolant, m / s
- G - coolant consumption, kg / s
- ρ - density of the coolant, can be taken for water 1000 kg / m 3
- f - The pipe cross section is located according to the formula π- · R 2, where R is the inner diameter of the pipe, divided into two
Data on consumption and speed is necessary to determine the conditional passage of the pipes of the junction, as well as the supply and pressure of circulation pumps. The forced circulation devices must create an overpressure that allows you to overcome the hydrodynamic resistance of the pipes and the shut-off valves. The greatest complexity is the hydraulic calculation of systems with natural (gravitational) circulation, for which the required excess pressure is calculated by the speed and degree of volume expansion of the heated coolant.
Pressure loss and pressure
The calculation of the parameters according to the ratios described above would be sufficient for ideal models. In real life and volumetric stream, and the coolant speed will always differ from the calculated systems at different points of the system. The reason for this is the hydrodynamic resistance to the movement of the coolant. It is due to a number of factors:
- Forces of friction of the coolant about the walls of the pipes.
- Local resistances of the flow, formed fittings, cranes, filters, thermostatic valves and other reinforcement.
- The presence of ramifications of the connecting and branching types.
- Turbulent twistings on turns, narrowings, extensions, etc.
The task of finding the drop in pressure and speed in different parts of the system is considered the most difficult, it lies in the field of calculations of hydrodynamic media. Thus, the friction forces of the fluid on the inner surface of the pipe are described by a logarithmic function that takes into account the roughness of the material and kinematic viscosity. With the calculations of turbulent twists, it is still more difficult: the slightest change in the profile and the shape of the channel makes each separate situation unique. To facilitate the calculations, two reference ratios are introduced:
- Kvs. - characterizing the bandwidth of pipes, radiators, separators and other sections approximate to linear.
- To ms. - Determining local resistance in various reinforcement.
These coefficients are indicated by pipe manufacturers, valves, cranes, filters for each individual product. The coefficients are quite easy to use: to determine the loss of pressure, the CMC is multiplied by the ratio of the square of the coolant speed of the coolant to the double value of speeding acceleration:
ΔH ms \u003d to MS (V 2 / 2G) or ΔP MS \u003d K MS (ρV 2/2)
- ΔH ms - pressure loss on local resistances, m
- ΔP MS - pressure loss on local resistances, pa
- To MS - local resistance coefficient
- g - Acceleration of free fall, 9.8 m / s 2
- ρ - density of the coolant, for water 1000 kg / m 3
The pressure loss on linear sections is the ratio of the bandwidth of the channel to the well-known bandwidth coefficient, and the result of the division must be erected into the second degree:
P \u003d (G / KVS) 2
- P - pressure loss, bar
- G - actual coolant consumption, m 3 / hour
- KVS - bandwidth, m 3 / hour
Pre-balancing system
The most important final purpose of the hydraulic calculation of the heating system is the calculation of such bandwidth values, in which in each part of each heating circuit flows a strictly dosed amount of heat carrier with a specific temperature than the normalized heat release on heating devices is provided. This task only seems complicated at first glance. In fact, balancing is performed by adjusting valves that limit the duct. For each valve model, it is indicated as the KVS coefficient for fully open state and the KV coefficient chart for different degrees of opening the adjustment rod. By changing the bandwidth of the valves, which, as a rule, are installed at the points of connection of heating devices, it is possible to achieve the desired distribution of the coolant, and hence the amounts of heat transferred to them.
There is, however, a small nuance: when the bandwidth changes at one point of the system, not only the actual flow rate on the sector under consideration changes. Due to the reduction or increase in the duct, the balance is changed in all other contours. If you take two radiator with different thermal power for example connected in parallel with the ongoing movement of the coolant, then with an increase in the bandwidth of the device standing in the chain first, the second will receive less heat carrier due to an increase in the difference in the hydrodynamic resistance. On the contrary, with a decrease in duct due to the adjustment valve, all other radiators standing on the chain further will receive a larger coolant volume automatically and will need additional calibration. For each type of wiring, balance the principles of balancing.
Software complexes for calculations
It is obvious that the execution of calculations is manually justified only for small heating systems that have a maximum of one or two contours with 4-5 radiators in each. More complex heat heating systems over 30 kW require a comprehensive approach when calculating hydraulics, which expands the range of tools used far beyond the pencil and sheet of paper.
To date, there is a fairly large number of software provided by the largest manufacturers of heating equipment, such as Valtec, Danfoss or Herz. In such software complexes, the same methodology that has been described in our review is used to calculate the hydraulics behavior. First, in the visual editor, an exact copy of the designed heating system is simulated, for which data on thermal power, the type of heat carrier, the length and the height of the pipelines used, used by the reinforcement, radiators and cooler coils are indicated. In the library of the program there is a wide range of hydraulic devices and reinforcements, for each product, the manufacturer has determined the operating parameters and basic coefficients in advance. If you wish, you can add third-party samples of devices if the desired list of characteristics is known for them.
In the work finals, the program makes it possible to determine the appropriate conditional passage of pipes, pick up sufficient supply and pressure of circulation pumps. The calculation is completed by balancing the system, while during simulation of the hydraulics, the dependences and the impact of changes in the bandwidth of one node of the system for all others take place. Practice shows that the development and use of even paid software products is cheaper than if the execution of the calculations was instructed to contract specialists.