Two-Gamma Jump Relations for Gaseous Detonation Waves

Research output: Contribution to journalArticle

Abstract

Accurate jump relations for Chapman-Jouguet (CJ) and overdriven gaseous detonation waves are derived. The difficulty in accurately approximating the energy equation in a perfect gas two-gamma detonation jump formulation is resolved by adjusting the authentic combustion heat release in terms of linearly approximated up- and down-stream sensible enthalpies at the CJ condition where it is exactly satisfied for CJ and well approximated for overdriven waves. The basis of the success of the derived two-gamma jump relations is explained. Explicit thermodynamic jump relations across a normal detonation wave are obtained. These approximate jump relations depend on the following four parameters: γ1, upstream isentropic exponent (or the gamma giving pertinent upstream sound speed for defining M1); γJ, CJ isentropic exponent (or the gamma giving pertinent sound speed for a CJ state); M1, upstream Mach number; and MJ, CJ Mach number. γJ and MJ can be obtained numerically, or experimentally with the derived jump relations. Comparisons of exact numerical and the present approximate calculation for jump conditions of CJ and overdriven detonations for methane- and hydrogen-oxygen systems show excellent agreement over a wide range of upstream Mach number, temperature, pressure, and mixture conditions.

Original languageEnglish
Pages (from-to)199-220
Number of pages22
JournalCombustion science and technology
Volume136
Issue number1-6
DOIs
Publication statusPublished - 1998 Jan 1

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology
  • Physics and Astronomy(all)

Cite this