Publications
Flame acceleration and DDT in ethylene/nitrous oxide at elevated pressures
Nitrous oxide and ethylene appear extremely promising as a bipropellant mixture for rocket propulsion systems. Earlier work with this bi-propellant mixture suggested that at high initial pressures, a deflagration will undergo extremely rapid acceleration and achieve transition to detonation in very short distances. To study the flame acceleration and DDT behavior as a function of initial pressure, tests were carried out in a closed, large L/d combustion tube and detonation pressures and velocities were measured. These mixtures were ignited using a high voltage spark ignition system and the results were compared to those which used a nichrome wire igniter. In addition, similar tests with ethylene-oxygen were performed in the same combustion tube for comparison. The detonation run-up distances from the nitrous oxide and oxygen tests and the dependence of run-up distance on initial pressure were determined and compared with those values from the nichrome wire igniter tests.