Accession Number : AD0870563

Title :   Ignition Property Studies.

Descriptive Note : Final rept. 15 Jun-30 Nov 69,

Corporate Author : OHIO STATE UNIV COLUMBUS AERONAUTICAL AND ASTRONAUTICAL RESEARCH LAB

Personal Author(s) : Diehl, Larry A. ; Rice, Eric E. ; Strauss, William A. ; Edse, Rudolph

Report Date : MAY 1970

Pagination or Media Count : 58

Abstract : The ignition delay times and the ignition temperatures of ethane-air and propane-air mixtures have been determined. The combustion properties of these fuels are compared with those of other potential scramjet fuels. The resonant wave patterns appearing in the fuel lines of mixing chambers have been examined by optical techniques. For mixing chambers without fuel flow (fuel line closed, which represents a simple resonance chamber ) it was observed that (1) shock waves travel into the fuel line, (2) the frequency and strength of these waves depends on the flow rate of the oxidizer, and (3) according to the data from the streak photographs, the temperature of the gas in the fuel line can exceed the thermal ignition temperature of combustible gas mixtures. Similar results were also obtained for low rates of gas passing through the fuel line. The relationship between unexplained autoignitions observed in flowing gas mixtures and the resonance phenomenon is discussed. (Author)

Descriptors :   *IGNITION), (*HYDROCARBONS, (*COMBUSTION, SHOCK WAVES), AIR, MIXTURES, METHANE, RAMJET ENGINES, GAS IONIZATION, IGNITION LAG, AUTOIGNITION, OXIDIZERS, SCHLIEREN PHOTOGRAPHY.

Subject Categories : Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE