Combustion Experiments for a Liquid Hydrocarbon Fueled Mach 5 Scramjet Engine Model

摘要

Some aspects of the supersonic combustion of liquid kerosene are brought into light by experimental research. Ignition and flame holding methods of liquid kerosene are verified. Ignition is possible by an electric spark igniter and hydrogen pilot flame. A certain level of ignition energy is required for the ignition at a given fuel atomization performance. And, conversely, a certain level of fuel atomization is required for a given ignition energy. Therefore, enough length for atomization is required before the flame holding cavity. Ignition cannot be achieved for the shortest model in the present study, the LO model, due to this problem. A cavity of 8 mm high and 20 mm long shows the successful flame holding capability for the present configuration. It is also possible, for certain conditions, to maintain the flame even without barbotage gas once ignited, but the combustion efficiency becomes inferior. The flame cannot survive without pilot fuel in any case. Better atomization performance or other methods such as fuel heating is required for this. But the present scheme may be acceptable for application to a real system because the pilot fuel flow is one-tenth of the main fuel flow on the mass basis.