Tu Baofeng, Zhang Xinyu, Hu Jun
College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
Entropy (Basel). 2020 Dec 15;22(12):1416. doi: 10.3390/e22121416.
In order to investigate the influence of steam ingestion on the aerodynamic stability of a two-stage low-speed axial-flow compressor, multiphase flow numerical simulation and experiment were carried out. The total pressure ratio and stall margin of the compressor was decreased under steam ingestion. When the compressor worked at 40% and 53% of the nominal speed, the stall margin decreased, respectively, by 1.5% and 6.3%. The ingested steam reduced the inlet Mach number and increased the thickness of the boundary layer on the suction surface of the blade. The low-speed region around the trailing edge of the blade was increased, and the flow separation region of the boundary layer on the suction surface of the blade was expanded; thus, the compressor was more likely to enter the stall state. The higher the rotational speed, the more significant the negative influence of steam ingestion on the compressor stall margin. The entropy and temperature of air were increased by steam. The heat transfer between steam and air was continuous in compressor passages. The entropy of the air in the later stage was higher than that in the first stage; consequently, the flow loss in the second stage was more serious. Under the combined action of steam ingestion and counter-rotating bulk swirl distortion, the compressor stability margin loss was more obvious. When the rotor speed was 40% and 53% of the nominal speed, the stall margin decreased by 6.3% and 12.64%, respectively.
为了研究蒸汽吸入对两级低速轴流压气机气动稳定性的影响，进行了多相流数值模拟和实验。在蒸汽吸入情况下，压气机的总压比和失速裕度降低。当压气机在额定转速的40%和53%下运行时，失速裕度分别降低了1.5%和6.3%。吸入的蒸汽降低了进口马赫数，增加了叶片吸力面边界层的厚度。叶片 trailing edge 周围的低速区域增大，叶片吸力面边界层的流动分离区域扩大；因此，压气机更易进入失速状态。转速越高，蒸汽吸入对压气机失速裕度的负面影响越显著。蒸汽使空气的熵和温度升高。蒸汽与空气在压气机通道内的热传递是连续的。后期空气的熵高于前期；因此，第二级的流动损失更严重。在蒸汽吸入和反向整体旋流畸变的共同作用下，压气机稳定性裕度损失更明显。当转子转速为额定转速的40%和53%时，失速裕度分别降低了6.3%和12.64%。 （注：trailing edge 直译为“后缘”，这里根据语境意译为“尾缘”更合适，但按要求未做修改）
