Comparative Heat and Mass Transfer in a Rotating Detonation Engine Model

Analyses of the heat and chemical species flux transported by molecular means and by mixture velocity (convection) are reported in this paper for a model of the rotating detonation engine using the large-eddy simulation (LES) approach, with the motivation being the relevance to the thermal management of the engine. The analysis is based on the two-dimensional (2D) unwrapped CFD model. Localized critical structures in the flow field (transverse detonation wave, shockwaves, and contact discontinuities) significantly affect the magnitudes and distributions of the heat flux. Convective transport is orders of magnitude greater than its molecularly transported counterpart. Surface heat flow rate and chemical species volume transfer rate per unit thickness are calculated, as are the Nusselt and Sherwood numbers. The results do not support an analogy between heat and mass transfer in the classical sense, as the differences in the results for the Nusselt number and Sherwood numbers cannot be explained by the differences in the Prandtl and Schmidt numbers. The implications of a 2D model for a 3D problem are briefly discussed.