摘要
应用时间推进法求解连续性方程、时均N-S方程、能量方程、理想气体状态方程及Yang＆Shihk-ε紊流模型,对含分流叶片的半开式叶轮及叶片扩压器组成的离心压缩机模型级级内三维粘性流场进行了数值分析,得出了与实测结果一致的性能曲线.在此基础上对叶轮等直径盖侧切削后的模型级进行了数值分析.计算及实验结果表明,切削后叶轮内部激波损失及扩压器吸力面侧低能区范围均减小;切削后叶轮盖侧的逆流区在扩压器前级的收缩作用下在扩压器内部基本没有扩大,有效降低了混合损失;叶轮盖侧切削后模型级的级性能优于原模型级,表明对模型级进行等直径叶轮盖侧切削可成为压缩机模型级设计的有效方法.为了加快收敛,计算时采用了隐式残差平均法及完全多重网格技术.
The time marching method was used to solve the control equations, and a computational analysis of the flow field in a centrifugal compressor with unshrouded impeller and vaned diffuser was presented. Emphasis was focused on the effect of the impeller shroud-cutting on the characteristics of the stage. The numerical analysis was carried out using three-dimensional Navier-Strokes codes with the Yang and Shih k-Ε two-equation turbulence model for closure. The calculations were performed with a central space discretization scheme, with second and fourth order artificial dissipation terms. The numerical procedure applied a four-order explicit Runge-Kutta scheme, coupled with local time stepping. A detailed comparison between the predicted and experimental data was performed in terms of pressure rise and efficiency characteristics, and favorable agreement was accomplished. Numerical and experimental results show that the stage characteristics under the new operating condition is improved after impeller shroud-cutting, which means that impeller shroud-cutting is an effective method in the design of the stage. The numerical procedure applies implicit residual smoothing and full multigrid technics for convergence acceleration.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2003年第9期979-983,共5页
Journal of Xi'an Jiaotong University
关键词
盖侧切削
半开式叶轮
时间推进法
多重网格
Boundary conditions
Compressors
Cutting
Impellers
Numerical analysis
Pressure
