Page 371 - Design and Operation of Heat Exchangers and their Networks
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Dynamic analysis of heat exchangers and their networks  355


                                                      (7.164)         (7.165)



                                                      MÞ
                                     t j
                              3   7  7  7  5          …,                  by
                                     e                2,
                              1   C  C  C   X U mk A ΔU nk 7  C  i ¼ 1,  ð  given
                                    U jk  M  m¼1      ^ j  t              are

                ! 7                  δ nj           ^ jk   X U mk A5  ^
             3    7 θ j 7e  7  5               13  C7  C7  C7  C7         (7.165)
                    + X U ik  10  CB  CB  CB  CB    U  M    m¼1           Eq.

                  M w  k¼1                                                in  C

                    sC i              M  + X U mk A@  m¼1  0  B  B  B  δ nj  B
                                    U ik                              T   B,and
                     δ ij               sC w,k      U ik U nk  M  + X U mk @  m¼1  as  Θ + BT + C ^  A,


                   U ik U jk  M  + X U mk  m¼1  0  B  B     δ ni  @ n¼1 B  sC w,k  form  Θ ¼ A e  matrices


                        sC w,k     M               M    n¼1     matrix  d e  dx  M M

                  M w  X  k¼1  1  C  C  C   X U mk A   X B  C  1  C  C  C   X U mk A   X  C  the  of
                    ¼ X 6             M    m¼1         M    m¼1  (7.164)  elements
             2    6  6  6  4        U jk            ^ jk  ^     in
                  M   j¼1                           U
                   d e i  θ  dx      δ ij             δ ij
                                    Δ e i U ik B                        i T .
                    C i       0    B  B  B  @  0    B  B  B  @  Eq.       The
                    _                             ! B
                                   _  C  _  C i     ^           express
                              2    6  6  4          _ U ik  C i U ik  ^ i  _  C  …, e M  θ
                                   M w  + XX 6  k¼1 6           to

                                   M   j¼1     2    6  6  4               e 1 , e 2 ,  θ
                                                   M w  k¼1 6   convenient  h  θ
                                                   M    1 XX 6  s  j¼1  is  It  e  Θ ¼ where
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