Investigation of High-Altitude Ignition Performance of Several Chinese Jet Fuels With Different Properties

Investigation of high-altitude ignition performance of several Chinese jet fuels with different properties has been conducted at a simulated altitude facility. Jet fuels were tested in a small pilot combustion chamber taken from an existing aeroengine. The fuels consist of Da-Qing oil, Da-Gang oil, Nan-Jing oil, Gu-Dao oil (so called as high density fuel) as well as a compound oil. Test results show that the lower the fuel density (its viscosity is also lower, but vapour pressure is higher), the better the high-altitude ignition performance. The high-altitude ignition performance of high density fuel is rather bad, but can be significantly improved by mixing it with a small quantity of low density oil (about 10 percent). Using a small flow number atomizer may obviously improve the weak ignition limit of the high density fuel, but the ignition velocity-pressure limit and the rich ignition limit are shrunk. Test results also show that prevailing theory model for spark ignition is feasible.