大推力液体火箭发动机试验用涡轮流量计结构优化设计

To improve the measurement accuracy of the DN600 turbine flowmeter for tests of the high-thrust rocket engine in the liquid oxygen, the turbine blades are optimized using the fluid simulation method combined with a 6DOF model. Firstly, a high-fidelity fluid simulation model is constructed based on the meter factor of the flowmeter in the water. Then, thermal-solid coupling simulation is used to create the equivalent model of cold shrinkage of the flowmeter in low temperature liquid oxygen, and the constructed fluid simulation model is used to obtain the equivalent relationship of the meter factor of the flowmeter in the water and oxygen liquid. Finally, orthogonal experiments are carried out to optimize the incoming flow angle of the pitch diameter, axial width, and coincidence of turbine blades based on the quantified equivalent relationship. The optimization objective is to minimize the linearity error of the meter factor. Results show that the meter factors of the flowmeter in water and liquid-oxygen are positively correlated; the optimized incoming flow angle, axial width, and coincidence are 55°, 55 mm, and 1 respectively; compared with the original turbine flowmeter, the linearity error of the meter factor for the optimized flowmeter is reduced by 0.104 5%, which significantly improves the measurement accuracy of the flowmeter.