Accession Number:

AD0730955

Title:

Supersonic Combustion and Burning in Ramjet Combustors.

Descriptive Note:

Rept. for 1 Apr 70-31 Mar 71,

Corporate Author:

OHIO STATE UNIV RESEARCH FOUNDATION COLUMBUS

Report Date:

1971-07-01

Pagination or Media Count:

60.0

Abstract:

At high initial pressures measured detonation wave speeds in hydrogen-oxygen mixtures are greater than those obtained from theoretical calculations while observed pressures of the detonated gas are less. Radiation from the combustion zone into the unburned gas appears to cause these deviations. Hydrogen-nitric oxide mixtures do not detonate at initial pressures below 10 atmospheres. A new shock tube employing a buffer gas section has been designed and constructed to investigate the cause of spontaneous ignitions in hydrogen-air mixtures at very low temperatures. Preliminary results indicate that at moderately high initial pressures low temperature spontaneous ignitions occur even in this facility. More experiments are needed to elucidate this behavior. Experiments with supersonic jets of hydrogen-chlorine mixtures showed that photochemical ignition with a mercury vapor lamp is possible. However, it appears that ignition occurs in the low speed boundary layer of the jet. Furthermore, it is practically impossible to generate high-speed jets of the mixtures at normal static temperatures because of the high stagnation temperatures required. Therefore, future studies will be made in a shock tube employing a transparent section for photochemical initiation of the shocked flowing gas. Detonation waves traveling through hydrogen-oxygen mixture in divergent channels maintain a constant speed although the pressure behind the wave decreases sharply. More experiments are underway to study this behavior. AuthoR

Subject Categories:

  • Combustion and Ignition
  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE