工业离心压缩机数值模拟方法及湍流模型研究

Research on numerical simulation methods and turbulence modelingfor industrial centrifugal compressors

为建立一套能够快速、准确预测工业离心压缩机基本级性能的数值模拟方法,针对某离心压缩机基本级试验装置开展了数值模拟方法的研究。探讨了数值模拟所采用的模型简化、网格型式、网格密度、边界条件、离散方法、湍流模型等,重点讨论了目前广泛使用的k-ε、RNG k-ε、k-ω、SST、SST-RM 5种湍流模型的特点和适用性。采用数值模拟方法对基本级试验装置在不同机器马赫数下的气动性能进行了预测,并与试验结果进行对比,发现数值模拟方法可以准确预测大部分工况,仅在近失速和近阻塞区与试验结果存在较大偏差。其中,采用SST-RM湍流模型的预测结果与试验结果最为吻合,这得益于其对流动分离的起始位置和分离区域的预测较其他湍流模型更为准确。研究结果对提高工业离心压缩机数值模拟精度有借鉴意义。

To develop numerical simulation methods capable of swiftly and accurately predicting the performance of industrial centrifugal compressors basic stages,a study was undertaken using a test rig set up as a centrifugal compressor basic stage.This research discusses model simplification,mesh type and density,boundary conditions,discretization methods,and turbulence models etc,emphasizing the characteristics and applicability of five commonly employed turbulence models(k-ε,RNG k-ε,k-ω,SST,SST-RM).These methods are utilized to predict the aerodynamic performance of the compressor basic stage under various Machine Mach Numbers and are assessed against experimental data.The findings indicate that the numerical simulation can precisely predict performance at most operational points,with significant discrepancies from experimental data happening only during near-stall and near-choke conditions.Among the models studied,the SST-RM turbulence model aligns most closely with experimental results,attributed to its superior accuracy in predicting the onset and area of flow separation compared to other models.The outcomes of this research hold implications for enhancing the accuracy of numerical simulations of industrial centrifugal compressors.