Experimental research on ignition and combustion properties of boron-containing fuels in mini-tubes

In order to obtain improved formulations of boron-containing fuels suitable for micro-thrusters, the effects of oxygen-fuel ratio and oxalic acid on ignition and combustion characteristics were studied using the thermogravimetry, the laser ignition test-bed and the iCAP-6300 emission spectrometer. The properties include flame appearance, ignition delay time, combustion time, combustion intensity, burning-rate and combustion efficiency etc. The results show that ignition delay time for samples without oxalic acid is shortened and burn-out rate increases with the increase of oxygen-fuel ratio. Meanwhile, burning-rate and combustion intensity are weakened. Nevertheless, after adding oxalic acid, ignition performance and burning efficiency improve significantly. To be specific, the descending value of ignition delay time range is from 545 ms to 595 ms, and the increasing value range of burn-out rate is from 31.41% to 32.67%, comparing to that of fules without oxalic acid.