Sooner or later owners of apartments, cottages, as well as specialists of warehouse, commercial, office and other premises face the problem of acquiring heating radiators. Regardless of whether the batteries are changed or a new heating system is changed, but the competent calculation of the required number of sections of any type of radiators will create an optimal microclimate for living or temporarily find people indoors, as well as provide the optimal temperature for storing goods. However, before calculating the heating radiator, it is necessary to determine the size of the product and the type of metal, since the thermal conductivity of all materials is non-etinak.
Content
Varieties of heating radiators
Currently, the main materials for the manufacture of heating radiators, which are presented in the article, perform steel, cast iron and aluminum. Considering that the various properties of materials used in the production of radiators affect the operational characteristics of the finished product of the non-DIA, then the entire variety of batteries is combined into 4 groups.
Cast iron radiators
Batteries made from cast iron enjoy high demand for several decades. However, unlike old copies, modern models are of greater aesthetics and allow them to concisely entertain them in the interior of various style without the use of protective screens.
Advantages:
- high resistance to aggressive impurities of the coolant;
- the ability to withstand significant hydraulic blows;
- good heat accumulating ability;
- a sufficient magnitude internal section eliminates the clogging of the radiator;
- durability;
- acceptable cost.
Disadvantages:
- the duration of the heating of the room at the initial supply of the coolant;
- the need for periodic color;
- the roughness of the inner surface contributes to the formation of various kinds of deposits, slightly reducing the performance characteristics of the product over time;
- mounting complexity due to high weight.
Despite all the advantages and disadvantages of cast iron radiators are ideal for battery as well as for the central heating system.
steel radiators
A huge variety of steel radiators manufactured by domestic and foreign manufacturers, is divided into:
- panel. Relative to other types of radiators are easy to design and more compact. thermal energy output in most panel radiators based on the principle of convection, so that there is uneven heating of the air mass. It would seem that the minimum number of welds must provide a good structural reliability. However, a small pipe section leads to a rather rapid clogging radiator for contaminated coolant containing various impurities, however panel radiators installed in apartment buildings is cautiously;
- tubular. The predominant feature of the tubular radiator is no sharp angles and varied performance design. In contrast, panel instruments, heat transmission through radiation and larger cross-section pipes are less susceptible to clogging and waterhammer. Thus docking joints formed by spot welding after a short operating period allowed to flow.
Advantages:
- a diverse range;
- good heat transfer at low thermal inertia;
- a wide price range, depending on the type of battery, sizes and used in the process of manufacturing technologies, designed to minimize various disadvantages.
Minuses:
- high demands for the quality of the coolant;
- low resistance to corrosion, especially when draining heating system for more than 2 weeks;
- the need for periodic staining;
- the average life rarely exceeds 10 years.
Steel heating radiators enjoy the greatest demand when installing in private homes or rooms heated from the autonomous system.
Aluminum radiators
Aluminum batteries began to produce relatively recently. Compared to iron products, steel, aluminum batteries are distinguished by a rather attractive design in a variety of performance.
Pros:
- the maximum level of heat transfer carried out by convection and thermal radiation;
- quick premises;
- excellent corrosion stability;
- low weight contributes to the simplicity of installation;
- acceptable cost.
Minuses:
- periodic vesting of the system;
- do not have resistance to hydrowards;
- it is impossible to use copper elements when installing the system, which in a short time derive a battery;
- a small operating period, rarely exceeding 10 years.
Despite a number of positive and negative points, some operational characteristics of heating radiators from aluminum depend on the method of manufacturing products.
Currently, aluminum batteries are carried out by:
- the casting when the required amount of pre-manufactured sections is connected to a single design by steel nipples and sealing pads. The main feature of radiators manufactured by the casting method is the production of products of rather complex forms, which allows you to choose the size of the radiator, based on the specific conditions of future operation. At the same time, the location of the compound of individual sections is rarely withstanding the crimping pressure of central heating systems;
- extrusion when the aluminum profile passed through special equipment is converted to the finished product. In contrast to cast, radiators manufactured by extrusion are greater resistance to pressure drops inside the heating system. At the same time remove or add sections from the finished product is simply impossible. The number of sections of the finished radiator varies within 3-16.
The species of aluminum radiators of heating are the anodized products, the production of which is carried out from the metal, which has passed better cleaning and exposed to anodic oxidation. Unlike simple aluminum, the anodized radiators have quite high resistance to chemicals present in the coolants of central heating. In addition, the connection of individual sections is carried out not by nipples, and the couplings recorded from the outside of the product, which increases the strength of the batteries in front of sharp pressure surges in the system. However, anodized instruments are an order of magnitude more expensive than their fellow, so they are not popular among the large circle of consumers.
Thus, it is not necessary to establish aluminum batteries into rooms with central heating, and to uniformly heating the rooms heated from the autonomous system, it is desirable to install a circulation pump.
Bimetallic radiators
Due to the ideal combination of steel and metal, bimetallic heating radiators turn the disadvantages used in the process of metals in the advantage of the finished design, which includes steel pipes for the movement of the coolant, which are externally enclosed in aluminum shell. Along with aluminum devices, bimetallic batteries are manufactured by casting and extrusion.
Pros:
- aesthetic appeal;
- excellent thermal conductivity inherent in aluminum batteries;
- good strength indicators;
- high resistance to hydraulic shocks;
- low weight;
- long period of operation.
Minuses:
- it is possible to clog the radiator due to the use of steel pipes of small diameter;
- high price.
Thus, choose bimetallic and other radiators worth considering the conditions of their future operation. For central heating systems, it is preferable to stop the selection on cast-iron and bimetallic radiators of the monolithic design, while the battery is suitable for the autonomous system, made of any type of metal. At the same time, you should not forget about the size of the size of the radiator you like and the place intended for installation.
Dimensions of radiators
To correctly calculate the sections of heating radiators, it is necessary to know the thermal conductivity of one section, which depends not only on the material, but also on the size of the finished product. At the same time, the dimensions of the radiators are selected with the following factors:
- Ideally, the length of the battery should occupy at least 50-60% of the window opening.
- The optimal height of the heating radiator \u003d distance from the window sill to the floor coating minus 15-20 cm, since the distance from the battery to the window sill when installing should be at least 8-10 cm, as well as the distance from the floor to the lower border of the battery, also vary within 8- 10 cm.
- The thickness of the battery is determined by the features of the planning, although the maximum heat transfer is achieved if the radiator performs 4-5 cm beyond the windowsill.
Considering the size of the product at the stage of calculating the required number of sections, the buyer insures itself from inaccuracies in advance when determining the required amount of heat for a particular room.
Calculation of heating radiators
The optimal radiator power is determined for each room separately, since the amount of heated air in various rooms is unlikely to be the same. Depending on the required degree of accuracy of the final result, one of the calculation methods is selected.
Calculation on Square
According to SNiP, for heating 1 m², 100 W thermal energy is necessary, so:
The number of sections \u003d the size of the room * 100 W / heat transfer section of the selected radiator (taken from the documentation that comes with the radiator).
For example, for heating the room with a width of 3 m and a length of 5 m bimetallic radiator, the average power of the section of which is 200 W, it will be necessary: \u200b\u200bthe number of sections \u003d 15 * 100/200 \u003d 7.5. Since the result turned out in the form of a fractional number, it must be rounded up to the integer in the direction of increasing, i.e. For heating room with an area of \u200b\u200b15 m² 8 sections are required that are broken by 2 radiator.
The calculation of the heating radiator in the area relates to a less labor-intensive method, which causes a rather approximal result.
Calculation by volume
Guided by SNiP, for heating 1 m³ in panel, brick houses without additional insulation measures, 41 W is required, and in insulated houses equipped with modern double-glazed windows, 34 W is enough. The calculation is made as follows:
Number of sections \u003d room volume (area * height) * 41 W (or 34 W) / power of the radiator section.
For example, the volume of the room located in the old Khrushchev is 37.5 m³ (3 * 5 * 2.5). As an acquisition, a cast-iron battery with a 100 W section heat transfer is considered. Based on their data, the number of sections \u003d 37.5 * 41/100 \u003d 15.375. Rounding the result, the desired value in 16 sections is obtained.
In contrast to the previous method of calculation, the determination of the number of sections by volume gives a more accurate result, but not the most reliable.
Using corrective coefficients
The peculiarity of the method is that when calculating the amount of heating radiators, various coefficients are taken into account, which to one way or another affect the preservation of heat in the room. The formula of the calculation has the following form:
Required radiator power \u003d room area * 100 W (heat rate for 1 m²) * KEP * KTP * CPL * KTE * KSTEN * KTIP * CRS / Power of the radiator section, where:
- KO - type of glazing (ordinary windows - 1.27; double double-glazed windows - 1.0; triple glass - 0.85);
- Ktep - the degree of thermal insulation of the walls (low or without insulation - 1.27; average - 1.0; high degree of thermal insulation, made using modern materials - 0.85);
- CLV - the ratio of the area of \u200b\u200bwindow openings to the floor of the room (10% -0.8; 20% -0.9; 30% -1.0; 40% -1.1; 50% -1.2);
- Kym is the minimum air temperature outside the window at the coldest time (-10 ° C-0.7; -15 ° C-0.9; -20 ° C-1,1; -25 ° C-1,3; -35 ° C-1,5);
- KSTEN - the number of outer walls (1-1.1; 2-1.2; 3-1.3; 4-1.4);
- KTIP - the coefficient corrective by the required power of the battery, based on the room located above the room (the attic is not heated - 1.0; residential apartment - 0.8; the attic heated is 0.9);
- Cles - ceilings height (up to 2.5 m-1.0; from 2.5 m to 3 m - 1.05; from 3 m to 3.5 m -1.1; from 3.5 m to 4 m - 1.15; from 4.5 m and above - 1.2).
For example, a room area located on the 3rd floor in a 5-storey panel house is 15 m² with a room height of 2.5 m. The outer insulation is made using cheap thermal insulation materials. The room has one window with a triple double glazing and, accordingly, one outer wall. The ratio of floor with window opening is about 10%. In winter, the temperature drops to -35 ° C. Radiator power - 200 W.
Required battery power \u003d 15 * 100 * 0.85 * 1.0 * 0.8 * 1.5 * 0.8 * 1.0 / 200 \u003d 6.12.
To heat the room, 7 sections of the radiator with a capacity of 200 W will be required.
Thus, the calculation of heating radiators, taking into account the correction coefficients, gives a more accurate result, which can be completely less than when determining the number of sections using approximate calculations.
