Компьютерное моделирование течения в микрофакельных горелочных устройствах с асимметричной подачей топлива

This article is devoted to the mathematical modeling of the isothermal flow in microjet burner devices with asymmetric jet supply of fuel by the introduction into the flow of an oxidizer. The studies were conducted on the basis of CFD modeling using the Ansys Fluent software. The Detached Eddy Simulation (DES) method, which is a hybrid approach, was used, in which Reynolds Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES) models are switched in different subregions of the computational domain. Particular attention in this article is paid to the comparative analysis of the flow characteristics in the presence and absence of flaps installed on the end surface of the flame stabilizers. According to the results of computer predictions, it is shown that, the flow pattern in the burner device changes significantly in the presence of flaps. These changes are also defined to be associated primarily with the formation of vortex structures in the region located behind the stern of the flame stabilizers. The analysis of the effect of flap length on different flow characteristics was performed. An increase in the flap length is shown to lead to a significant increase in the length of the reverse flow zone behind the flame stabilizer. This length is proved to exceed the flap length the greater, the shorter the flap. The features of the velocities distribution within the zone of reverse flows for various values of the flap length are revealed. The analysis of the fields of root-mean-square pulsations of velocity in the considered physical situations was carried out. The subregions corresponding to the highest levels of these pulsations are defined to be located near the boundary of the zone of reverse currents remote from the end of the flame stabilizers. The highest level of these velocity pulsations is revealed to meet the conditions for the absence of flaps on flame stabilizers. Some prospects for further research consist primarily in the analysis of the flow structure in the burner devices considering the conditions of reacting flows. Moreover, the study of the regularities of the mixing of fuel and oxidant is of considerable interest, as well as the burning out of fuel and the formation of temperature fields in the combustion zone.