Available Technologies

Technology

Liquid rocket engines experience various difficulties, including ignition for engine restart in extreme low temperature and vacuum conditions, as well as acoustic noise and combustion instabilities, which can even couple with the fuel inflow and magnify themselves.

UAH researchers have developed an acoustic engine igniter that uses a resonance tube to not only ignite the propellant, but also to mitigate combustion instability. By placing the resonance tubes at appropriate locations within the combustion chamber, combustion instabilities can be avoided and acoustic noise can be reduced.

Using the resonance tube for ignition also allows for more efficient use of the fuel by enabling ignition to occur within milliseconds. This is especially advantageous for engines that require frequent restart at extremely low temperatures, such as Attitude Control Systems (ACS) in space.

A typical ACS is turned on and off frequently in the extreme conditions of space while in service. Thus, current attitude control systems avoid using liquid bi-propellant engines, and instead use the cold gas thruster or the hypergolic engine with lower performance. By eliminating the slow ignition problem of the liquid propellant engine, this invention allows it to be used in the ACS efficiently.