The influences of the shear coaxial injector parameters on the combustion performance and the heat load of a combustor are studied numerically and experimentally. The injector parameters, including the ratio of the oxidizer pressure drop to the combustor pressure （DP ）, the velocity ratio of fuel to oxidizer （R V ）, the thickness （WO ）, and the recess （HO ） of the oxidizer injector post tip, the temperature of the hydrogen-rich gas （TH ） and the oxygen-rich gas （TO ）, are integrated by the orthogonal experimental design method to investigate the performance of the shear coaxial injector. The gaseous hydrogen/oxygen at ambient temperature （GH2 /GO2 ）, and the hot hydrogen-rich gas/oxygen-rich gas are used here. The length of the combustion （LC ）, the average temperatures of the combustor wall （TW ）, and the faceplate （TF ） are selected as the indicators. The tendencies of the influences of injector parameters on the combustion performance and the heat load of the combustor for the GH2 /GO2 case are similar to those in the hot propellants case. However, the combustion performance in the hot propellant case is better than that in the GH2/GO2 case, and the heat load of the combustor is also larger than that in the latter case.
