Propulsive Performance of Hypersonic Oblique Detonation Wave and Shock-Induced Combustion Ramjets

Abstract

A comparative study is presented of the propulsive characteristics of hypersonic detonation wave and shockinduced combustion ramjets. The same ramjet design methodology is used to assess the propulsive performance of both types of ramjets. The lower ‐upper symmetric Gauss ‐Seidel scheme combined with a symmetric shockcapturing total variation diminishing scheme are used to solve the Euler equations describing thetwo-dimensional hydrogen/air combustible e owe eld with nonequilibrium chemical reactions including 13 species (H2, O2, H, O, OH, H2O, HO2, H2O2, N, NO, HNO, N 2, and NO2). Results obtained for e ight Mach numbers 12< ‐ M1 < ‐ 16 and for a e ight dynamic pressure of 67,032 Pa (1400 psf) show that combustor entrance temperatures Tce (or inlet compression ratios ) substantially lower than the near ignition values of hydrogen/air mixture, adopted for the generation of a near Chapman ‐Jouguet oblique detonation wave in the combustor, entail signie cant performance augmentation. For the considered range of e ight Mach numbers and value of e ight dynamic pressure, the thrust of a shock-induced combustion ramjet is maximum for 650 <‐ Tce < ‐ 700 K, and at this point the combustion is entirely shock induced. The thrust generation can be enhanced by more than 10% and the fuel specie c impulses improved by more than one-third over their magnitudes corresponding to maximum thrust detonation wave ramjets.