Fuel Delivering System For SCRAMJET Ground Test

Supersonic Combustion Ramjet ( SCRAMJET ) is being more and more emphasized because of it's magnificent foreground in military and aerospace applications. At present, most of the domestic researches about SCRAMJET are focused on ground test. Extremely expensive cost is a limitation laying on SCRAMJET research campaigns. Changing the reality of testing one case during one fire to testing several cases during one fire is a reasonable way to reduce SCRAMJET ground test cost.Based on the analysis of fuel delivering system, a strategy which can realize step like fuel flow rate switch through dynamic combination of apertures is drawn out. And detail design of mechanism and control system is accomplished. Control software is developed under LabVIEW environment. Computer based measurement and control system realized dynamic combination of apertures by means of operating digital output ports. The problem of water hammer occurred in the fuel delivering system was eliminated by means of optimization on control parameters. Other details of the system are also taken into consideration to accommodate to the quick switching among different flow rates. The succeeding tests proved that the fuel delivering system was full functional.The dynamic apertures combination based fuel delivering system drawn out in this paper has the advantage of more simple structure, more reliable operation and less construction cost. The time needed for flow rate switch is only limited by valve switch time. The system is well satisfies the requirement of testing several cases during one fire in the SCRAMJET ground test research. The dynamic apertures combination method also has opportunity of adopting during SCRAMJET fly test.