It is also important to choose the correct height and diameter of the chimney. Incorrect calculation of at least one parameter will affect traction and efficiency. Errors that may be made during the design and construction of a chimney in a residential building or bathhouse, often lead to more serious consequences: fire, the need for financial costs for remodeling and etc. Therefore, it is so important to comply with regulatory requirements for pipe construction.
How to calculate the diameter of the chimney
The content of the article
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How to calculate the diameter of the chimney
- Swedish method
- Accurate calculation
- Chimney Diameter Chart
When designing a chimney, it is necessary to choose the material to use. And the material largely depends on what fuel will be used for heating. After all, the chimney is designed to remove the combustion residues of one fuel, and will not work with another. For example, a chimney made of bricks works perfectly with wood, but is not suitable for heating appliances that work with gas fuel.
In addition, a correct calculation of the diameter of the home pipe is necessary. If the chimney is used for one heating device, the problem can be solved by looking at the technical documents provided by the factory that manufactured the device. And if several different systems are connected to one pipe, then to calculate the chimney, you need to know the laws of thermodynamics, professional calculation, especially the diameter of the pipe. It is wrong to assume that a larger diameter is needed.
Swedish method
Among the different methods for calculating the diameter, the optimal scheme is important, especially if the devices are low temperature and long burning.
To determine the height, the ratio of the cross-sectional area of the chimney pipe to the internal combustion chamber is taken into account. The height of the pipe is determined according to the schedule:
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Where f is the area of the cut of the chimney, and F is the area of the furnace.
Let, for example, the cross-sectional area of the furnace F be 70 * 45 = 3150 sq. cm, and the cross section of the chimney f - 26 * 15 = 390. The ratio between the above parameters is (390/3150) * 100% = 12.3%. Having checked the result with the graph, we see that the height of the chimney is approximately equal to 5 m.
Important! This calculation method is more suitable for fireplace appliances, because the air volume inside the furnace is not taken into account here.
Important! In the case of installing a chimney for complex heating systems, it is important to calculate the parameters of the chimney.
Accurate calculation
To calculate the desired cross section of the chimney, it is imperative to take into account all its characteristics. For example, you can perform a standard calculation of the size of the chimney connected to a wood stove. Take such data for calculations:
- the temperature of the combustion waste in the pipe is t = 150 ° C;
- the speed of passage through the waste pipeline is 2 m / s;
- the rate of combustion of firewood B is 10 kg / h.
If you follow these indicators, you can do the calculations. For this purpose, calculate the amount of exiting combustion products by the formula:
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Here V is equal to the amount of air that is required to burn fuel at a speed v =10 kg / hour. It is equal to 10 m³ / kg.
It turns out:
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Then calculate the desired diameter:
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Chimney Diameter Chart
Now relevant are the diameters tables compiled for various chimneys, since many prefer to install finished pipe elements from various materials. To easily understand these various materials and learn how to choose the right parameters, documents with regulatory data entered in special tables have been developed. The relevant parameters are indicated here. To calculate the required dimensions, you can use these tables.
Attention! It should be remembered that the cross section of the flue pipe must be greater than or equal to the cross section of the internal channel of the heater.
Exact tables of calculated diameters of the flue pipe for its correct operation is calculated in accordance with the technical the parameters of all elements, in accordance with the recommendations of specialists, materials of the smoke exhaust channel or with the help of tables diameter - power.