Experimental study of hydrogen-rich/oxygen-rich gas-gas injectors

Five types of coaxial injectors were investigated experimentally using hot hydrogen-rich gas and oxygen-rich gas,which were respectively provided by a GH2/GO2hydrogen-rich perburner and a GH2/GO2oxygen-rich preburner.The injectors were the shear coaxial injector,the oxidizer post expansion coaxial injector,the fuel impinging coaxial injector,the central body coaxial injector,and the shear tri-coaxial injector.The characteristic velocity effciency and the combustor’s wall temperatures were obtained for different design parameters through the experiments.It can be concluded that angles of the oxidizer post expansion and the fuel impinging have little influence on the combustion performance and the wall temperatures.The contact area between fuel and oxidizer and the mass flow rate have signifcant impacts on the combustion performance.The shear tri-coaxial injector has the best combustion performance but also the highest wall temperatures among the fve types of injectors.