Page 247 - Modelling in Transport Phenomena A Conceptual Approach
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PROBLEMS                                                             227

           where

                                                                                (3)


           c)  Show that the integration of  Eq.  (2) leads to





                                          +-                  &(u  - 1)      }  (4)
                                            ip2 tan-'  (2p - 1 + u [(2/P) - 11

           where
                                       u3  = 1 - (1 + p3p                       (5)



           7.11  Rework Example 7.3 if the rate of  reaction is given by




           a) For the filling period show that the governing differential equation is given by




           Using the substitution
                                               1  du
                                          CA = --                               (3)
                                               ku dt
           show that Eq.  (1) reduces to






           Solve Eq.  (4) and obtain the solution as





           Note that Eq.  (2) indicates that CA = CA,  at t = 0.  Obtain the same result from
           Eq- (5).
           b) Show that the governing differential equation for the unsteady-state period is
           given in the form
                                     - +kC2, -I--  = -
                                                      CA,
                                                 CA
                                     dCA
                                     dt          7     7-
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