Supersonic combustion heat flux in a rotating detonation engine

Five components of heat flux, viz: conduction, q_cond^″, sensible mass diffusion, q_diff^″(s), formation mass diffusion, q_diff^″(o), sensible convection, q_conv^″(s), and formation convection, q_conv^″(o) have been analyzed extensively in this paper for the unwrapped model of the rotating detonation engine (RDE), using an explicit large-eddy simulation (LES) approach with a kinetic mechanism consisting of eight reaction steps and seven chemical species. The results shown are from averaged fields obtained after the attainment of the quasi-steady state condition. The maximum static pressure occurs at the transverse detonation wave, with a value that is one order of magnitude higher than the relatively uniform values that are found in most part of the domain. By y≈0.0044m, which is roughly one-tenth of the axial distance in the domain with (x,y)ε[0,0.1]×[0,0.04] m, most of the reacting species (H₂,O₂) have been depleted at all transverse locations. From the mass averaged magnitudes of the heat flux components, it has been found that q_conv^″(o), has the largest contribution, followed very closely by its sensible counterpart, q_conv^″(s), whose magnitude is roughly half of that for the formation enthalpy heat flux. This is followed (in magnitude) by q_diff^″(o) and q_diff^″(s), which are of comparable values and are over three orders of magnitude smaller than the convective heat flux components. The conductive heat flux q_cond^″ is roughly an order of magnitude smaller than the mass diffusion values. The Nusselt number and heat transfer coefficient for the present problem are significantly higher than those encountered in low-speed, non-reacting flow fields.