Page 175 - Fundamentals of The Finite Element Method for Heat and Fluid Flow
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TRANSIENT HEAT CONDUCTION ANALYSIS
                                        0.5 T = −45.0°C    Insulated     T l  = −0.15°C       167
                                                      T s  = −10.15°C
                                                           4

                                      Figure 6.14 A one-dimensional solidification problem


                        side face is subjected to a liquidus temperature of −0.15 C. The solidus temperature is
                                                                        ◦
                              ◦
                        −10.15 C. Determine the temperature distribution with respect to time if the latent heat of
                        solidification is 70.26, ρc p = 1.0 and k = 1.0. Draw the temperature variation at a distance
                        of unity from the left side with respect to time.
                           The unstructured mesh used to solve this problem is shown in Figure 6.15(a). The tem-
                        perature contours at a time of four units is shown in Figure 6.15(b) and the temperature
                        variation at a point of unit length from the left face is shown in Figure 6.15(c). These results
                        show a close agreement with existing results (Lewis et al. 1996).







                                              (a) Unstructured mesh, nodes: 202, elements: 328





                                                  (b) Temperature distribution at t = 4
                                            5

                                            0
                                                                   Explicit
                                           −5
                                         Temperature  −10


                                          −15

                                          −20
                                          −25
                                             0  0.5  1   1.5  2  2.5  3   3.5  4
                                                             Time
                                                 (c) Temperature distribution at a point
                                                 (1, 0.25) with respect to time
                        Figure 6.15 Solution for the phase change problem using the effective heat capacity
                        method
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