Mult ltipha hase F Flo low M Models ls i in S n STAR-C -CCM+ Simo mon L n Lo
Eule lerian M Mult ltipha hase F Flo low M Models ls i in S n STAR-C -CCM+ � Gr Granu nula lar f flo low – Mixing of multiple particle phases � Mult lti-c -compone nent nt b boili ling ng – Binary mixture evaporation � Popula lation b n bala lanc nce – Adaptive MUSIG � Mult ltipha hase r rhe heolo logy y – Suspension – Emulsion
DE DEM A Approach – h – M Mixing ng a and nd C Coating ng o of P Particle les
Mult lti-p -particle le R Rotary Dr y Drum – m – P Particle le s segregation n 3 3 mm 4 mm 4 mm 5 mm 5 mm 6 mm 6 mm mm Particle le s segregation i n in t n trans nsverse p pla lane ne o of d drum m
EMP A Approach - M h - Mult lti-p -particle le R Rotary Dr y Drum m Poly ly-d -dispersed p particle les – – 3 3mm, 4 mm, 4mm, 5 mm, 5mm, 6 mm, 6mm. mm. Average p particle le v velo locity v y vectors i in t n trans nsverse p pla lane ne o of d drum m
Multi-particle Rotary Drum – P Particle le v velo locity Streamwise velocities at x=0 on the transverse plane, rotating speed 11.6rpm
Mult lti-c -compone nent nt b boili ling ng mo model l � Evaporation o n of mu mult lti-c -compone nent nt f flu luids. . – Applications refinery and distillation processes.
Evaporation o n of a a b bina nary mi y mixture
Evaporation o n of b bina nary mi y mixture: P : Pent ntane ne & & Do Dodecane ne Ga Gas Heat Heat Te Temperature x P Pent ntane ne x Do Dodecane ne Void Vo Liqui Li uid d fraction n
Adaptive M MUS USIG M IG Model l An E n Eule lerian p n popula lation b n bala lanc nce me metho hod f for p poly ly-d -disperse mult mu ltipha hase f flo lows. .
Adaptive M MUS USIG M IG Model l Mass a and nd nu numb mber d dens nsity a y are r redistributed b between ne n neighb hbour g groups so t tha hat e each g h group ha has t the he s same me ma mass b but ne new d diame meters. . 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 d d d d
Adaptive M MUS USIG - Dr IG - Drople let b breakup t thr hrough a h an o n orifice Sauter Mean Diameter Breakup Rate (log scale) Turbulent-induced breakup Shear-induced breakup
Suspensions – relative viscosity model Krieger-Dougherty model
Suspensions – Eulerian multiphase Two-fluid formulation The momentum equation for phase k is From the suspension balance model Fluid stress is pressure with viscous term and shear particle stress term Particle stress is Morris and Boulay total stress
Suspensions – relative viscosity models Morris and Boulay model Total particle stress is: web.mit.edu
Suspensions – pipe flow modelling Modelling results of Hampton et. al NMR suspensions in pipe experiments At volume fraction of particles = 0.3 The Morris and Boulay relative viscosity model is capable of causing particle migration towards the centre of the pipe. When the normal stresses are turned off then no particle migration occurs. Kn = 2
Emulsions Surfactant stabilised emulsions share many properties of suspensions as the fluid particles can be approximated as solid particles. - As the volume fraction of the dispersed phase is increased the effect of maximum packing leads to divergent viscosity, - eventually a phase inversion occurs.
Emulsions Pressure Drop in STAR-CCM+ Modelling the pressure drop in pipes, (experimental data from Dr. Jose Plasencia) “Pipe flow of water-in-crude oil emulsions: Effective viscosity, inversion point and droplet size distribution” Jose Plasencia, Bjørnar Pettersen and Ole Jørgen Nydala, Journal of Petroleum Science and Engineering Volume 101, January 2013, Pages 35–43 Crude oil A and seawater emulsion in horizontal pipe of diameter 2.21 cm, At a velocity of 0.44 m/s (laminar regime). Interestingly with models that have no negative normal stresses, Pressure drop is over- estimated
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