“…This will result in chemical kinetic limitations on the H 2 -air ignition and combustion processes. On the other hand, this limitation can partiallybe circumventedif an elevated concentration of oxygen is used in the test gas to increase the collision rates as suggested by Bakos et al 7 However, BenYakar 22 has shown that, in high-enthalpy ows, presented in this paper, ignition of hydrogen, injected transversely into a freestream of air, can be achievedin the near vicinity of the injector, even at low pL values. If ignition is achieved at low pressures, it is, therefore, likely that autoignition will occur at higher pressures because the Damköhler and Reynolds numbers increase linearly with pL in a realistic system.…”