Modeling of Conjugate Problem of Friction and Heat Exchange in Transpiration Cooling of Blades of Gas Turbines

A model is developed for numerical calculation of heat exchange in nozzle blades of high-temperature gas turbines with transpiration cooling. The model includes the joint numerical calculation of convective heat exchange, heat exchange in transpiration channels and conduction heat exchange in the blade solid body. Results are given which characterize the structure of the external flow, flow in transpiration channels and in areas of blowing-out. Distributions of the cooling efficiency, heat fluxes, constants of friction along the turbine nozzle blade are presented and the feasibility to get the accepted wall temperature level with the gas temperature 1800 К at the turbine entrance and the relative cooler consumption G_cool = 5.9% is determined. It is noted that the loss factor is by 1.6% higher than that of a traditional blade.