Accurate measurement and evaluation method of axial compressor efficiency under the influence of multiple factors

Abstract In order to improve the effectiveness of compressor efficiency measurement results under the influence of complex factors, several research work have been carried out, such as inverse connection of thermocouple suitable for efficiency measurement under low pressure ratio and small temperature rise conditions, torque efficiency correction considering the mechanical loss of high speed gearbox under various working conditions, and identification of the impact of seal cavity leakage flow on efficiency measurement. Compared with the conventional connection method of thermocouple, the inverse connection method of thermocouple shows obvious advantages in efficiency measurement under low pressure ratio and small temperature rise conditions. At medium and low speeds, the conventional simplified correction method will lead to the high measurement results of torque efficiency after installing the high speed gearbox. The accuracy of torque efficiency measurement can be improved by adopting the improved correction method. Increasing the oil supply pressure of the high speed gearbox or reducing the oil supply temperature will increase the mechanical loss of the high speed gearbox. The air flow in the compressor bearing seal chamber will leak into the flow passage through the labyrinth clearance, resulting in discontinuous changes of the inlet/outlet flow of compressor.