Design and experimental study on high flowrate multi-element gas-gas injector chamber

To investigate the combustion characteristics of high flowrate injector in the multi-element injector chambers having interaction between the elements, based on high flowrate gas-gas injector studies in the single-element condition, a multi-element injector equipped with seven shear mixing elements was deigned, which can simulate effectively the real engine. The shear mixing element had high H₂/O₂ velocity ratio and tapered O₂ post tip. Numerical simulation and hot-fire tests were carried out with this injector using the optimal design of the injector layout. Steady operations were obtained in all these tests, and the injector showed benign heat environments on the faceplates and cylinder walls. Combustion efficiency above 99% was gotten for this injection element in the flowrate of 3.7 times of SSME (space shuttle main engine) main injection element.