Numerical investigation of strut parameters effects on performances of a cavity-based ramjet combustor

A numerical investigation of strut parameters for enhancing fuel-air mixing and combustion in a ramjet combustor is carried out. The inlet Mach number of isolator is 0.4 with a total temperature of 600K. The strut, located at the channel symmetry axis, acts as injector, and a ramped wall cavity, located downstream of the strut, acts as the flameholder. The commercially available software package Fluent is used to research the effect of different strut parameters. Reynoldsaveraged Navier Stokes equations with species conservation equation are solved based on the finite volume method. The Realizable k-e turbulence model is used in this work This paper uses the method of orthogonal experimental designing, parametric modeling of strut configurations is performed by the orthogonal design with 5 factors at 3 levels. The combustion efficiency and total pressure losses are set as objective functions of combustion performance of ramjet combustor. And the axial variations of the mixing efficiency, combustion efficiency and total pressure losses are calculated to investigate the influence of strut parameters on the combustor performance. It is found that the strut makes the mixing efficiency, combustion efficiency and the specific impulse of the combustor improve in a remarkable extent, although it makes the total pressure recovery coefficient reduce. And moderate strut parameters can help to improve combustion performance.