回流器冲角对于压缩机模型级性能影响的研究*

摘要

Based on constructing the numerical model (including the impeller, vaneless diffuser and deswirl) of a centrifugal compressor, its inner flow field was numerically simulated and calculated under off-design conditions by software CFD NUMECA. Based on the off-design performance curve and information of inner flow field, it was found that the derived entrance width of deswirl was too big and caused a flow separation on the suction side of the deswirl blade. Aiming at this problem, the measures that reduced the entrance width appropriately and carried out corresponding modeling, meshing and numerical simulation were adopted. Then the improved off-design performance curve and information of 3-D flow field were obtaind, which had showed a significant improvement over the original structure.%　　通过建立离心压缩机模型级（包括叶轮、无叶扩压器和回流器）的数值计算模型，利用Numeca软件对其内部流场进行数值模拟及变工况计算，得到该级的变工况性能曲线及内部流场信息。经过变工况性能分析和流场分析，发现由冲角公式反推出的回流器进口宽度过大，导致其叶片吸力面侧流动分离，产生漩涡。针对这一问题，适当减小回流器进口宽度，并进行相应的建模、网格划分和数值计算，得到改进后的变工况性能曲线及三维流场信息，较原结构有明显改善。