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370                                  12.  Compressible  Navier-Stokes  Equations



                           dW?     d   ON
                                      8Qy
                                                              0       0     0
                                                              1       0     0
                         Vy
           -[M]  +  [N y]  =                                           4
                                           >                  0             0
                              -(! - &V -  (i - £W - &f    a -  &)« (! -  &)« £ J
                                                                           (12A.5)
                  dW 2
            [N}  =
                  ~dQ~y
                                                     0        0     0
                                                                          (12A.6)
                                                      1       0     0
            ™  = - e                                 0        4     0
                               2
                                          2
                      -(I - £) v  -  (l -  £)u  -  ^ f  (i -  £)u (! -  £)*  £

         Appendix    12B
         Treatment    of he Region     Close o he     Boundaries
                         t
                                              t
                                                 t
         for  Eq.  (12.5.4)
        For the region which has at  least one boundary  side, Eq.  (12.5.4)  is approximated
        differently  from  Eq.  (12.5.5),

         On  the  bottom  subdomains   i ? ^ ,  close  to  the  wall  j  =  1
            9Qi,l  _   ^i+1/2,1  _  E i-l/2,l  F i,l+l/2  _  -^2,1-1/2
              dt              Ax                  Ay
                             E
                        1   ( v)i+\/2,\  ~  ( ^ ) i - l / 2 , l  ( ^ ) z , l + l/2  ~  ( ^ ) z , l - l / 2
                     +
                        Re~           Ax                        Ay
         Note that  1 -  1/2  => 0

                        £, 2 +  1,1  — ^ 7 - 1  1  2  ^ °
                          '
                                 ^ 2 - 1 , 1
                at           2Ax               Ay
                          1   C^v)i+1/2,1  _  (Ev)i-1/2,1  (^v)z,l + l/2  _  (^v)i,0
                       +                             +
                         Re             Ax                      zAy

                      ^2+1/2,1+1/2  ~~ ^2+1/2,1-1/2
         (%)z+l/2,l
                                 Ay
                      (^2 + 1,1 + 1 +  ^2,1 + 1 +  ^2+1,1 +  ^2,l)/4  ~  ( ^  + 1,1-1/2  +  ^ 2 , l - l / 2 ) /  2
                                                  Ay
                      K + 1 , 1 + 1 +  ^2,1 + 1 +  ^2+1,1 +  ^2,l)/4  -  (^2+1,0  +  U ii0)/2
                                              Ay
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