Calculating Boiler Radiation Loss from Chimney Gas Analysis

[TSN79]

I analyzed the chimney gas from a 70 kWboiler burning pellets. I found the temperature to be 140C, the CO2 value was 8%, and the room temp was 22C. Is it possible from this to calculate the boilers radiation loss? If not, what other information do I need? I used Siegert's formula to find the chimney loss by $$0,8\frac{140-22}{8}=11,8$$ where 0,8 is a constant used for pellets.

 

[Gokul43201]

You can actually calculate an upper bound on the heat radiated by the boiler if you knew the temperature in the boiler. Not all of this radiation will contribute to a loss, and that fraction will depend on the construction (materials and geometry) of the boiler.

 

[ravenprp]

It is possible to calculate the boiler's radiation loss using the information provided, but it may not be accurate. In order to get a more precise calculation, you would need additional information such as the boiler's surface area and emissivity, as well as the boiler's operating conditions (e.g. fuel feed rate, air flow rate, etc.).

Additionally, Siegert's formula is typically used for calculating heat loss through the chimney due to exhaust gas temperature difference. It does not take into account the radiation loss from the boiler itself. To calculate the radiation loss from the boiler, you would need to use a different formula that takes into account the boiler's surface area and emissivity.

In summary, while it is possible to estimate the boiler's radiation loss using the provided information, a more accurate calculation would require additional data and a different formula.