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Using Nanofluids to Control Fines Migration in Porous Systems  197


























              Figure 4.10 Profile of water saturation along 1-D porous medium (Dashed line: with-
              out nanoparticles; Solid line: with nanoparticles coinjection. The difference between
              two lines represents the “oil-bank” attributed to nanoparticles effects (Yuan, 2017a)).


              pretreatment affecting both fines migration and waterflooding efficiency
              is also characterized. By implementing the splitting method and stream-
              function transformation already described, 3 3 3 governing equations can
              be reduced to a 2 3 2 auxiliary subsystem containing only particles com-
              ponents (nanoparticles and fines) and a lifting equation involving only
              phase saturation, as shown in Eq. (4.17).
                 Water component:

                                @G    @F         1        S w
                                    1    5 0; G 5  ; F 52                (4.17a)
                                @x D  @ϕ         f w      f w
                 Fine particles component:

                                    @C FP  @S a  @S s
                                         1     1    5 0                 (4.17b)
                                     @x D   @ϕ   @ϕ
                 Kinetics equations for fine particles attachment and straining:

                                     8
                                       Λ a C FP
                                                    ð
                                     <    ffiffiffiffiffiffi ; σ a , σ cr x D ; C NP Þ
                                @S a  5  p                               (4.17c)
                                @ϕ   :  2 x D
                                         ð
                                       σ cr x D ; C NP Þ
                                         @S s  Λ s C FP                 (4.17d)
                                         @ϕ  5 p ffiffiffiffiffiffi
                                              2 x D
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