节点文献
引气量对多级轴流压气机性能影响的数值研究
Numerical Investigation of Bleed Rate on Performance of Multistage Axial Compressor
【摘要】 以NASA 74A压气机前3.5级为研究对象,利用源项法探究级间引气量变化对压气机总体性能和内部流动的影响。结果表明:引气量越大压气机总体特性变化越显著,10%引气量下压气机流量范围拓宽25.72%,相比于未引气的压气机最高效率点效率增加5.6%,压比增加2.76%,而引气后进口气流冲角减小以及叶背处流动分离减弱所带来的气体流通量的增加是效率提升的主要原因;引气使得压气机稳定裕度升高,当最佳引气量8%时其稳定裕度增大21.80%;引气提高了压气机进口流量,但两者变化量不完全一致,在最高效率点处引气,引气量与进口质量流量增加量基本相等,然而,当低于最高效率点流量时,小流量点的增加量大于引气量,而大流量点则相反,这决定了出口流量的增减,影响了压气机总压比;引气对于气流周向角度影响更大,对径向角度的影响主要集中于引气位置附近。
【Abstract】 The research focuses on the first 3.5 stages of NASA 74A compressor, utilizing the source term method to explore the impact of the interstage bleed rate on compressor overall performance and internal flow characteristics. The results demonstrate that as bleed rate increases, there are more significant changes in compressor overall performance. Specifically, compared to the peak efficiency point without bleeding, the mass flow range expands by 25.72%, efficiency rises by 5.6% and total pressure ratio increases by 2.76% at 10% bleed rate. Efficiency in-creasing can mostly be attributed to mass flux increasing which is caused by attack angle reduction and control of flow separation. Additionally, interstage bleeding enhances stall margin, with an optimal bleed rate of 8% resulting in a stall margin increase of 21.80%. It should be noted that the increase in inlet mass flow and bleed rate is not in agreement completely, but both are essentially equalized at the peak efficiency point. For lower mass flow points, the bleed rate is lower than the increment in inlet mass flow, while the phenomenon behaves the opposite way for higher mass flow points, which determines the variations of outlet mass flow and impacts on total pressure ratio in the meanwhile. Furthermore, bleeding has a greater influence on circumferential angle deviation compared to radial angle deviations which caused by bleeding are primarily concentrated near bleed positions.
【Key words】 multistage axial compressor; bleed rate; source term method; stall margin; overall performance; axial velocity;
- 【文献出处】 燃气轮机技术 ,Gas Turbine Technology , 编辑部邮箱 ,2024年03期
- 【分类号】V232;TK474.8
- 【下载频次】29