Effect of energy addition parameters upon scramjet nozzle performances based on the variance analysis method

As an important component, the nozzle produces most of thrust in scramjets. A new concept of increasing the aerodynamics of the scramjet nozzle with energy addition is presented. The essence of the method is to create a heated region in the inner flow field of the scramjet nozzle. In this paper, the two-dimensional coupled implicit compressible Reynolds Averaged Navier-Stokes (RANS) and Menter's shear stress transport (SST) turbulence model have been applied to numerically simulate the flow fields of the single expansion ramp nozzle (SERN) with and without energy addition. The variance analysis method coupled orthogonal experimental design has been introduced to investigate the effects of the energy addition parameters on the aerodynamics (i.e. thrust coefficient CT, lift coefficient CN and pitching moment coefficient CM) of the scramjet nozzle. The numerical results show that the proposal of energy addition can be an effective method of increasing force characteristics of the scramjet nozzle, the thrust coefficient CT, lift coefficient CN and pitching moment coefficient CM increase by 1.55%, 47.27% and 2.53% respectively. The effect of the energy addition density on the aerodynamics of the scramjet nozzle is substantial, and it must be foremost when considering the design of the scramjet nozzle. The findings suggest that scramjet nozzle design and performance can be benefitted from the application of energy addition.