Experimental study on the combustion performance of a turboshaft engine annular combustor

Abstract

Efficient application of trapped vortex combustion technology is a hotspot in the aerospace field. This paper describes a turboshaft engine combustor based on this technology, named as mixed-flow trapped vortex combustor (MTVC). MTVC utilizes stable vortex structure formed in cavity to promote combustion stability. RP-3 aviation kerosene required for combustion is directly injected into cavity, which continuously supplies energy to combustor. Combustion performance of MTVC with different inlet aerodynamic parameters and fuel-air parameters was studied experimentally on full-ring test rig, including combustion efficiency, pressure loss and outlet temperature profile. According to the experimental findings, MTVC has very high combustion efficiency under the testing conditions of this paper, all exceeding 96%. Pressure loss coefficient is positively correlated as the square of inlet Mach number. Pressure distribution of MTVC is largely consistent with inlet velocity. Outlet temperature profile is not a straight line at radial height, showing a distribution trend of high temperature in the middle of combustor outlet, and low temperature at both ends of combustor outlet. Peak temperature is essentially at 0.6 times combustor outlet height. There is a cyclical variation in circumferential direction. The variation between combustion efficiency and aerodynamic parameters is also obtained in this paper.