船用内旁通流道的压损特性研究

对某船用汽轮机内旁通流道特性试验进行了数值计算分析：基于可压缩N-S方程,利用Spalart-Allmaras湍流模式及有限积分法,采用四面体非结构性网格,对内旁通流道进行了数值模拟.预测了内旁通流道不同开度及旁通流道不同入口Ma的全压损失系数,计算结果与试验结果吻合良好.通过数值计算,得到了对内旁通流道广泛适用的计算方法,为慢速机组内旁通流道及旁通阀的设计和性能分析提供了重要依据.

Study on pressure loss characteristics of internal bypass flow path for marine steam turbine

As marine steam turbine often need to operate at part load operation with high efficiency, most of the marine steam turbines in China had adopted the structure with internal bypass flow path. In view of the great effects on the characteristics of internal bypass flow path on the overall performance of the steam turbine, a numerical calculation and analysis based on tests of characteristics of internal bypass flow path of one set of marine steam turbine were presented in this paper. On the basis of compressible N-S equation, a numerical simulation was developed for bypass flow path, using Spalart-Allmaras turbulent mode and finite integral method with teltrahedron non-structural mesh. The total pressure loss coefficients at different openings of internal bypass flow path and different Mach number at the inlet of bypass flow path were estimated. It can be shown that the calculation results agree wel with the test results. The numerical developed in this paper can provide an important basis for the design and performance analysis for the internal bypass flow path and bypass valve.