透平级中湿蒸汽均/异质凝结流动的数值方法

从物性计算、对流通量求解、非结构网格局部加密3个方面发展了Euler-Euler框架下湿蒸汽非平衡态均/异质凝结流动的数值方法。在对流通量方面,给出了真实物性下均、异质凝结共存时的Jacobi矩阵、Roe和AUSM+通量。在物性计算方面,提出了基于Taylor级数表(tabular Taylorseries expansion,TTSE)方法的3自由度湿蒸汽物性表,有效平衡了复杂状态方程下精度和计算量之间的矛盾,并在此基础上探讨了两种不同的水珠温度处理方法对模拟精度的影响。针对非平衡态凝结对网格密度较高的要求,开发的非结构有限体积求解器能方便地利用悬挂节点(hanging node)方法对凝结区网格进行局部加密。喷管和透平级均/异质凝结算例表明:该数值方法具有良好的精度和鲁棒性,能较好地反映均异质凝结的流动特点。

Homogeneous/heterogeneous condensing flow modeling in turbine cascades

Numerical methods were developed to simulate homogeneous and heterogeneous condensing flow using the Euler-Euler framework with real steam properties,convective fluxes,and local mesh refining.The convective flux models implement the Jacobi,Roe and AUSM + flux with real steam and water properties.The steam properties are stored in a three-dimensional tabular Taylor series expansion(TTSE) table which balances the accuracy of the complex equation-of-state and the computational complexity.The system is used to analyze two droplet temperature treatments and their impact on the simulation.An unstructured finite volume method(FVM) solver is used that can easily refine the mesh in the condensing region using hanging nodes.An analysis of a nozzle and a turbine stage show that this method is accurate,robust,and reflects the characteristics of the homogeneous and heterogeneous condensation.