Analysis of Rotating Detonation Wave Engine

Rotating Detonation Wave Engine (RDE) due to its promising potential as a propulsive and power generation device has been researched worldwide based on both numerical and experimental investigations. The thermodynamic analysis has been of importance prior to the commencement of the experimental investigations as the set conditions could be established with ease. The flow field behind the detonation wave has been quite complex due to oblique shock wave, contact surface between combustion products of detonation wave and shocked combustion products and the expansion waves. The simultaneous establishment of the flow parameters has been of importance to the success of understanding the RDE. The enthalpy values at different states have provided the energy conversion to kinetic energy as a result of expansion of the product gases in the RDE flow field. Stability of the oblique shock wave attached to the detonation wave has been crucial for obtaining optimum performance of RDE. The intersection of oblique shock polar and the Prandtl - Meyer expansion characteristics has given the conditions under which the oblique shock remains attached to the detonation wave and be a part of the triple point. Under all the set conditions, the stability of the oblique shock has been ascertained. In the present analysis, the specific thrust for the present configuration using H2-air is 1374 Ns/kg compared to a value of 1347 Ns/kg reported in the literature for a stoichiometric composition. The marginal difference has been due to the different input conditions ahead of the detonation wave. This has given credence to the results of the analytical work based on gas dynamic and thermodynamic relationships. The practical implications of this analytical work have been brought out.