The goal of the present work is to investigate the effects the heat exchanger can have on the acoustic response of the flames(flame transfer function) in a boiler. In compact condensing boilers the distance between the burner and heat exchanger is small enough to cause intense interactions. That is why we constructed a simplified CFD model of a boiler to study various cases with different distances between the burner and heat exchanger. Results show that the flame transfer function changes considerably when the flame impinges on the heat exchanger tube. The gain can acquire values above one for low frequencies due to incomplete combustion and the phase can be increased because of flame deformation and stretch. These results help analyze the acoustic behavior of the flames in such situations with more detail.
|Title of host publication
|COMBURA'15 Combustion Research and Application, 7-8 October 2015, Soesterberg, The Netherlands
|Published - Oct 2015