Page 91 - Handbook Of Multiphase Flow Assurance
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86                             4.  Hydraulic and thermal analysis

                                                      3
                                                        2
                                                     L ρβ ∆ T     buoyancy
                                        Grashof Gr =      g    =
                                                        µ 2     viscousforce

                                                    hd   convective heat transfer
                                       Nusselt  Nu =   =
                                                     k   conductive heat transsfer
                                                     a   Sc   thermal  diffusion
                                         Lewis Le =    =    =
                                                   D AB  Pr   mass  diffusion
                                                     µ
                                                     ρ    viscousmasstransfer
                                       Schmidt  Sc =    =
                                                    D AB  diffusive mass transfeer

                                                    K  L  convective mass transfer
                                     Sherwood   Sh =  c  =
                                                     D    diffusive mass trannsfer
                                    ρ vD         fluid  inertia
                                       2

                        Weber We =       droplet  =         = = interactionoftwo fluidsatinterface
                                      σ interface  surfacetension

                                                          advectiveheattransfer
                                     Peclet  Pe  = PrRe  =
                                              HEAT
                                                          diffusive heat traansfer
                                                      advectivemasstransfer
                                        Pe MASS  = Sc Re  =
                                                       diffusive mass transfer
                                                         D
                                          Graetz Gz     =  Hydraulic  RePr
                                                    HEAT
                                                            L
                                                       D
                                               Gz MASS  =  Hydraulic  Re Sc
                                                          L
                   The use of dimensionless numbers may be useful in understanding flow characteristics. For
                 example Beggs and Brill used Froude number in coordinates to present a flow regime map.
                   Someday multiphase software tools will be able to plot each of these dimensionless values,
                 which may lead to new understanding of multiphase flow phenomena and improved ma-
                 chine learning pattern recognition.


                 Software

                   Software can be broadly classified as capable of solving steady state and transient flow mo-
                 tion. Both classes include both empirical and mechanistic models, with the possibility to use
                 two phase flow as in vapor-liquid, three as in gas-liquid-water or four phases with addition
                 of a drilling mud fluid. In some instances solids transport may be added so flow of up to five
                 phases may be modeled.
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