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Comparison Between Finite Difference Methods, Finite Elements and Finite Volume Methods for the Prediction of Heat Transfer Phenomena in a 2d Composite Block

Using numerical method for heat transfer is cheaper than experimental methods .In this articles heat transfer in solid plate with difference materials has been analyzed. Computation times and the accuration of solving problems have been compared in difference numerical methods. This problem has been solved with general finite difference method in three form of implicit, explicit, Crank Nickolson by a code, which is written by FORTRAN 90. Tecplot is used to view the results such as temperature distributions. The problem has been solved by finite volume software such as fluent and finite element software such as ansys to compare and test the results driven from FORTRAN code. In finite volume method the velocity and pressure fields in steady state form has been solved. Momentum equations in x,y directions has been solved by first order upwind and the continuity and energy equations has been solved by first order upwind method. The finite element problem has been solved by using a 2-D, 8-node thermal element. The element has one degree of freedom, temperature, at each node. The 8-node elements have compatible temperature shapes and are well suited to model curved boundaries. Convection or heat flux (but not both) and radiation may be input as surface loads at the element faces. In general, comparison the finite volume method has the better results in comparison with the others method such as finite difference or finite elements also the finite element method is better than finite difference method for predicting the heat transfers in a 2dcomposite block. In finite difference (Explicit) by refining mesh concentration, the computational time has been reduced but increasing mesh concentration for reducing the computational time has a limit and after passing this limit the computational time will be constant,Computational time will be reduced by using the explicit method in comparison of the Crank Nickolson method. An implicit method shows the better Temperature distribution near the boundary in comparison with two other methods. Difference form of finite difference method (implicit, explicit, Crank Nickolson) shows equal temperature distribution far from the boundary limits.