Page 297 - Fundamentals of The Finite Element Method for Heat and Fluid Flow
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                        SOME EXAMPLES OF FLUID FLOW AND HEAT TRANSFER PROBLEMS









































                        Figure 9.31 Forced convection heat transfer from spherical heat sources mounted on the
                        wall. Surface mesh of an in-line arrangement


                        surface mesh used for the in-line arrangement. The bottom adiabatic wall, in which the
                        no-slip boundary conditions are assumed, is refined near the spheres. For the staggered
                        arrangement, the same density of nodes is assumed, and this results in a smaller number
                        of nodes and elements.
                           The results are mainly presented in terms of the heat transfer and fluid flow quantities
                        of interest. The non-dimensional heat transferred from the spheres to the fluid has been
                        calculated from the computed temperature distribution. In particular, the average Nusselt
                        number for each sphere, Nu s , is obtained by using the following integral:
                                          1               1                1     ∂T
                                   Nu s =     (Nu s ) p dA =   ∇T · n dA =         dA        (9.5)
                                         A s  A           A s  A           A s  A ∂n
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