Experimental investigation of the turbine in a turbopump for a liquid rocket engine with a 75-ton force thrust

This study investigates the performance of a supersonic impulse turbine in a 75-ton thrust liquid rocket engine. The Korea Space Launch Vehicle-II has a liquid rocket engine that generates a 75-ton force thrust. This engine uses a powerful turbopump to introduce the propellants into the combustion chamber. Supersonic impulse turbines are employed in turbopumps to generate a high specific power under conditions of a low flow rate of the turbine driving gas. In this study, performance tests were conducted for the supersonic impulse turbine using high-pressure air at the turbine testing facilities at the Korea Aerospace Research Institute. The tests were performed in ranges including the design point and off-design points. The results indicate that the turbine efficiency increased with increasing velocity ratio and was more strongly affected by the rotational speed than the pressure ratio. A drop in efficiency occurred in the range below the design pressure ratios owing to the occurrence of shock waves in the nozzles. 2018 The Korean Society of Mechanical Engineers.