组合压气机气动优化设计与试验验证

Aerodynamic optimal design and test validation of a combined compressor

以轴流-离心组合压气机为研究对象,根据机械加工改铸造加工节约生产成本的改进目标,对离心叶轮和径向扩压器进行优化设计。全三维数值仿真结果表明,优化设计方案提高了该组合压气机的性能和喘振裕度,达到了优化设计目标。优化设计虽然恶化了离心叶轮与径向扩压器尖区流动,但对离心叶轮叶中及以下区域和后排通道内流动的改善较明显,且对前面的轴流级叶排内部流动基本无影响。试验验证表明,优化设计压气机的性能满足设计指标要求,优化设计技术得到充分验证,为后续类似设计积累了经验。

A certain compressor combined axial stage with centrifugal stage was taken as the subject investigated,and the centrifugal impeller and the radial diffuser were optimal designed,according to the improvement target,which replace casting processing by mechanical operations to save the cost.The full three-dimensional numerical simulation results show that the optimal designing scheme improved the performance and surge margin of the combined compressor,and finally met the optimal design goal.Although the optimal designing worsens the tip-area flow of impeller and radial diffuser,it hardly influences the internal flow of the axial rows,and improves remarkably the flow under the mid-span of the impeller instead,especially for the passage flow of backward rows.The test results show that the characteristics of the optimal designed combined compressor basically achieved the design goal,and the optimal design technology has also been validated.Meanwhile,design experience has been accumulated for similar design.