One pipe put into oven, the oven keep 200 C, the water will flow through the pipe, I want to calculate the outlet water temp of pipe.  how to define 200C temp in the flow simulation? one is : Input data--General setting--wall conditions--wall temp ,set 200C; Another is : Boundary condition--real wall--wall parameters--Tw:200C

Could you tell me which one is correct?  I'd appreciated if you can input you comments.