A computational and experimental study of turbulent combustion in the combustion chamber for premixed fuel (methane) and oxidizer (air) in a wide range of excess air ratio (a = 1.6-3.6) was performed. The features of the influence of the inhomogene- ous character of the field of fuel concentration at the inlet to the combustion zone on the emission of pollutants, as well as low- frequency and high-frequency oscillations in the combustion chamber were considered. The calculation methods used RANS and URANS. To carry out the calculation studies of the effect of inhomogeneous field of fuel concentration (method of RANS) in the entire range ofa , it proved necessary to modify the model of turbulent combustion to account for after-burning of the flame front. Due to URANS method, in three-dimensional case, the low-frequency mode (consumables) vibrations, whose frequency is significantly lower frequency of the first acoustic mode were obtained.
|
