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186                           6.  Inviscid Flow Equations for  Incompressible Flows


                           4>i+ij  -  2(/>jj +  </>j-ij  01+1J  -  01-1J
                       Vi                        + Vi
                                                           2Arj
                            +         (*0 2           = 0                 (6.3.12a)

         or  with  (3 =  A£/Aq

                  ®l(/>i,j  +  a2<fo+i,j  +  ^30i-l j  +  <l>ij+l - <t>i,j-i = l  0  °  (6.3.12b)
                                                          i
                                                       +
                                                         0
                                                           j
                                                            -
                                                               =
         where
                                                                2
                                                             2
                         l
          a i  =-2fa?/?  2  + ),  a 2 =f7?|9  2  +  ^ ( ^ ) A  a 3  =  T / / ? - ^ ^ ) / ?  (6.3.13)
         The  boundary  conditions  are
                               i  =  0,     00, j  =  cos£j/r/o           (6.3.14a)
                               i  =  I+l,    * - 0                       (6.3.14b)
                                             orj
                               3  =  0,     g-                            (6.3.14c)

                               j  =  J + l ,                             (6.3.14d)
                                            % - *
         Using Eq.  (6.3.14a),  Eq.  (6.3.12b)  at  i  — 1 can  be  written  as

             a i 0 i j  +  O202J  +  01J+1  +  01J-1  =  - " 3 00 ,j  =  - « 3  cos£j/riQ  (6.3.15a)
         Using  Eq.  (4.5.14)  in  Eq.  (6.3.14b),  Eq.  (6.3.12b)  at  i  =  I  can  be  written  as

                                        a
             (ai  + -a 2J  4>IJ +  f «3  -  o 2J  0/-1J  + 0/j+i  +  0/j-i  = °  (6.3.15b)
         Using Eq.  (4.5.14)  in  Eq.  (6.3.14c),  Eq.  (6.3.12b)  at  j  =  1 can  be  written  as
                         4 \                           2
                    a                                                     (6.3.15c)
                     l  +  o J 0i,l  +  «2^i+l,l  +  «30z-l,l  +  «0i,2  =  0
         Using Eq.  (4.5.14)  in  Eq.  (6.3.14d),  Eq.  (6.3.12b)  at  j  =  J  can  be written  as
                        4 \                           2
                                 a
                   «1  +  o j  ^hJ  + 20i+l,J  +  «30i-l,J  +  g0i,J-l  =  0  (6.3.15d)
         Using Eq.  (4.5.6),  with  U  now  equal  to  </>, Uj  =
                                                      -J

                                       *1           0iJ
                                       ^2           02,i
                                  0 =                                     (6.3.16a)
                                       *i           0z,j


                                       £/           0/,i
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