尾迹影响涡轮叶片表面换热特性的算法研究

One of the main factors causing unstable flow in the turbine cascade channel is the propagation of upstream blade unsteady wake. The unsteady wake advances the transition from unstable laminar flow to turbulent boundary layer on the surface of turbine blades, leading to an earlier transition. The influence of unsteady wakes on the surface heat transfer characteristics of turbine blades was predicted based on boundary layer transition theory. Firstly, the unsteady wake-induced time-averaged intermittency factor was in-troduced to correct the turbulence intermittency factor. Secondly, the phase-averaged turbulence intensity was used to predict the onset of transition induced by the unsteady wake. Finally, the turbulent viscosity coefficient generated by the unsteady wake was introduced to correct the effective viscosity coefficient in the laminar region of the blade. Results show that the computational method and improvement for the unsteady wake influence on turbine blade surface heat transfer characteristics have been well validated in relevant experimental Systems, significantly improving the accuracy of heat transfer calculations under the unsteady wake influence.