Page 395 - Modelling in Transport Phenomena A Conceptual Approach
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9.3.  HEAT TRANSFER WITH CONVECTION                                 375


                                1.2

                                 1
                                0.8
                              e
                                0.6
                                0.4

                                0.2

                                0
                                  0    0.2   0.4   0.6    0.8
                                                 5
                Figure 9.13  Variation of  8 as a function of  with Br as a parameter.



            In dimensionless form, Eq. (9.3-88) becomes
                                                   fl

                                                                            (9.3-89)

                                                   Jo
           where
                                                                            (9.3-90)

            Substitution of Eqs.  (9.3-71) and (9.3-87) into Eq.  (9.3-89) gives

                                                                            (9.3-91)




            Calculation of the Nusselt number for the bottom plate

           The heat flux at the bottom plate is expressed as


                                                                            (9.3-92)

           Therefore, the Nusselt number becomes

                                                                            (9.3-93)
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