Heat dissipation of bimetallic heating radiators and its proper use
The level of costs for maintaining comfortable conditions in residential, public, office and other premises depends on the efficiency of these devices. This wording contains a mention of the importance of specific operating conditions. Nevertheless, in any case, when the correct calculation of bimetallic heating radiators is needed, it is necessary to take into account not only the power of the sections declared by the manufacturer. It is imperative to find out how much money and effort will have to be spent so that the heat transfer of the product is used rationally.
Heat flow and heating system: basic concepts and definitions
Any bimetallic heating radiator produces heat transfer to the surrounding space using the following processes:
- movement of heated air masses (convection);
- heating surrounding objects by radiation;
- an increase in the temperature of substances during their direct contact (heat exchange).
Each of them is described by complex physical formulas and scientific theories, which are only partially used in practice. To design a heating system of any level of complexity, you need to make a calculation that will help you find out how many sections of a bimetallic heating radiator should be used so that this power is sufficient.
If such calculations are made with a certain margin, then even on the coldest days, the temperature required by users will be maintained in the premises. On the other hand, a more accurate calculation will help establish the actual required lower power limit, which will reduce the amount of initial and operating costs.
How to calculate the number of sections of a bimetallic heating radiator
A very approximate, but often used in practice, calculation is based on the following provision: about 0.1 kW is enough to heat one unit of area (sq.m.). The heat transfer of a section of a bimetallic device is assumed to be approximately equal to that provided by a similar part of the heat transfer of cast-iron radiators, if an appropriate replacement is made. If there are two external walls in the room, you need to increase the power by 25-30%. The available volume can be taken into account if the area is multiplied by the height and the nominal standard (41). It corresponds to the minimum power recommended for residential applications.
Of course, such a calculation of sections of heating radiators is not accurate. It does not include specific climatic conditions, actual building insulation parameters, door and window units. More accurately calculate, or bimetallic, only specialized specialists will be able to. They apply formulas with correction factors.
What features should be considered when choosing a radiator model
In the passports for specific devices, manufacturers must indicate the power of one section in kW. It is it that should be used in order to find out how many such elements are needed in order to provide sufficient heat flow. Below is placed, which contains some data on radiators of various types. They can only be used for general evaluation.
|
Radiator type |
Approximate power of one section |
Peculiarities |
|
cast iron |
In standard domestic models, it is no more than 160-180 watts. |
Passport data are sometimes given for too high a temperature that is not often used in practice. In reality, the nominal heat flux can be 40-50% lower. |
|
Steel |
It is approximately equal to that which cast-iron models have. |
Radiators with more fins work more efficiently using convention processes. |
|
Aluminum |
In some models, it reaches a value of 190-200 watts. |
They are most susceptible to corrosive processes and can be safely installed only in private systems where careful control of the quality and composition of the coolant is possible. |
|
Bimetallic |
The most advanced heating radiators of this type are capable of providing a nominal heat flow of more than 200 W when using only one section. |
The cost of the most efficient bimetallic batteries can be higher than that of aluminum counterparts. But they are able to maintain their excellent consumer parameters for a longer time. |
How heat transfer can be increased without major costs
The most important thing for the rational use of energy resources is the correct calculation. Only he will show how many sections of a certain type will be needed to maintain a comfortable temperature in the room using the existing coolant supply system. But the efficiency of a set of equipment can also be increased using the following information:
- The heat flux is reduced if the device is sequentially painted without first removing the old layers.
- The most effective is direct and diagonal connection. In these options, the hot coolant is supplied to the upper part, and the outlet is carried out from the bottom. Single pipe communications are less good. In this case (bottom connection), energy consumption will increase by 40% and even more.
- By reflecting the heat flow from the wall with the help of a screen attached to the radiator, you can direct it towards the room. It will heat up faster.
- They can have a negative impact: pollution of the radiator channels; too close to the floor, window sill, walls; inaccurate installation with violation of the horizontal. By eliminating such shortcomings, it will be easier to use the maximum potential of the heater.
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