Analysis of transient radiation-convection coupled effects on the HP turbine blade heat load with hot streak inlet

Hot Streak (HS) and thermal radiation are the two important factors affecting the heat transfer process in High Pressure (HP) turbine stage, while the previous investigations were limited in studying either of them independently. In order to investigate the combined effects of the HS and radiation, the present study is aimed at unsteady convection-radiation coupled simulations with regards to HS and uniform inlet conditions. Three dominant radiative factors were analyzed in details. Compared with the uniform cases, it is found that there are two high temperature regions in the rotor passages of HS cases. The maximum temperature increase of the vane surface is about 40 K caused by radiation. As the HS changes the temperature distribution, the radiative heat flux is redistributed and a portion of radiative heat flux transfer from the stator passage to the rotor passage. The turbine inlet radiation mainly affects on the guide vane, whereas the gas radiation has a more significant influence on the rotor blade heat load.