Physics-based flame dynamics modeling and thermoacoustic instability mitigation

[摘要] (cont.) In order to investigate the perforated-plate stabilized flame dynamics, a theoretical model was developed to predict the dynamic heat-release response to inlet velocity oscillations. In this configuration, the dynamics are driven by the coupled effects of the flame-wall interactions and the flame-acoustic wave interactions, generating burning velocity and flame area oscillations. The model predictions under different operating conditions were compared with the experiments and good agreement was obtained. As the heat loss to the plate increases, the plate;;s surface temperature rises, the flame temperature decreases, and the burning velocity oscillations become more significant. In order to verify and relax some model assumptions, two-dimensional simulations were performed in the same configuration utilizing a detailed chemical kinetic mechanism and allowing the heat transfer between the gas and the perforated-plate. The primary results of the simulations support the conclusions of the theoretical model, and show the significant impact of the heat transfer to the plate on both the steady flame characteristics, and the unsteady dynamic flame response.

[发布机构] Massachusetts Institute of Technology