Page 365 - Modelling in Transport Phenomena A Conceptual Approach
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9.2.  ENERGY TRANSPORT WITHOUT COiWECTIOA                           345



















           Figure 9.6  Representative temperature distributions in a rectangular wall with
           constant generation.


           Type I1 boundary condition
           The solution of  Eq.  (9.2-8) subject to the boundary conditions

                                                   dT
                                  at  z=O      -k-=qo
                                                   dz                      (9.2-15)
                                  at  x=L      T=TL
          is given by


                                                                           (9.2-16)

          Note that when R = 0, Eq.  (9.2-16) reduces to Eq.  (G) in Table 8.2.  Further
          simplification of  Eq.  (9.2-16) depending on whether k and/or  8 are constant are
          given below.
           R Case  (i) k = constant

          In this case Eq.  (9.2-16) reduces to
                         k (T - TL) =  [lz!R(u) du] dz + qoL (1 - i)       (9.2-17)



          When !R = 0, Eq.  (9.2-17) reduces to Eq.  (H) in Table 8.2.

          W  Case (ii) k = constant; !R = constant
          In this case Eq.  (9,216) reduces to
                                    ?I2 L2
                                                    +
                           T=TL+- 2k  [1- (323 y (1 -         ;)           (9.2-18)
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