for heat transfer between Turbine and it surroundings do we consider heat transfer occurs at the surface temperature of Turbine for example 500K or we just consider T, the temperature on the boundary where heat transfer occurs, the same as T0? ■

I hope someone will follow and help. I know it to some extent. T depends on the boundry we select and when T is not constant we use some thermodynamic average temperature, but I dont know what people do for exergy analysis of the Turbine when dealing with nonadiabatic Turbine? Is there any exergy accompanying Q? ■

Then shouldn't I count on the Knowledgeable members? I need to understand. Do you suggest me any book? I read many books on exergy like those written by Seider, Bejan, Moran and still am confused. ■