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Problems with boundary condition
Posted Dec 6, 2012, 5:13 PM EST Heat Transfer & Phase Change Version 4.2 1 Reply
We've tried to solve a problem. Here it is:
It has a system of two concentric pipes. An opaque liquid enters to the inner pipe with entrance velocity and temperature known. The space between the pipes is evacuated, but the inner mantle of the outer pipe acts as a heat source that is maintained at constant temperature.
We've represented the problem as a system of three rectangles, being the inner one the inside with the liquid, the middle one is the pipe wall, and the outer is the space between both pipes. The radiative condition is OK, but the convective one has been troubling us. When trying to model this condition, we cannot select the pipe's inner boundary. We thought separating rectangles with a little distance could be a solution, but then, the solver couldn't converge.
Any help will be welcome. Please, this is urgent!