性能试验是评价涡轮部件性能的最主要方式，其中效率测量精度对试验结果至关重要，但会受到诸多过程因素影响。本文基于低压涡轮性能试验结果，分析了进出口流场、封严气温度/流量、雷诺数、叶尖间隙、机械损失和效率定义对涡轮试验效率的影响，为涡轮性能试验与测试方案设计，试验数据分析提供参考。试验通过设置与主流相同温度的封严气和在进气段外机匣铺设保温层，实现了进口总温径向偏差小于2K，周向偏差小于1K。根据涡轮出口移动测量结果，受感部周向分布可能带来0.14%的试验效率偏差。低压涡轮封严气与主流温比增加0.1，效率降低0.11%，流量增加1%，效率降低0.29%。低压涡轮效率随雷诺数下降而降低，从起飞到巡航，雷诺数变化导致的低压涡轮效率差异超过1%。涡轮特性不同状态点，径向间隙不同带来的效率偏差达到0.66%，数据分析时须修正间隙影响。此外，机械损失和效率定义对试验效率的影响可达到0.3%以上。
Turbine rig test is the most important way to evaluate the turbine performance in which the accuracy of efficiency measurement is very important to the test results, but it will be affected by many process factors. Based on the results of low-pressure turbine (LPT) rig test, this paper analyzes the effects of inlet and outlet flow field, sealing flow temper-ature/mass flow rate, Reynolds number, tip clearance, mechanical loss and efficiency definition to turbine test efficien-cy, which provides reference for turbine performance test scheme design, instrumentation design and test data analy-sis. By setting the sealing flow with the same temperature as main flow and covering thermal insulation material at inlet outer casing during test, the radial deviation of the inlet total temperature is less than 2K and the circumferential deviation is less than 1 K. According to the measurement results of turbine outlet movement, the circumferential distri-bution of probes may bring 0.14% test efficiency deviation. When the temperature ratio of seal gas to main flow in-creases by 0.1, the efficiency decreases by 0.11%, the flow rate increases by 1%, and the efficiency decreases by 0.29%. LPT efficiency decreases as Reynolds number falls, the reduction in efficiency from take off to cruise is above 1%. t different state points of turbine characteristics, the efficiency deviation caused by different radial clearances reaches 0.66%, so the clearance influence should be corrected in data analysis. In addition, the definition of mechani-cal loss and efficiency can affect the test efficiency by more than 0.3%.
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