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Numerical modeling of nanofluids By Dr. ********************* ******************

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Presentation on theme: "Numerical modeling of nanofluids By Dr. ********************* ******************"— Presentation transcript:

1 Numerical modeling of nanofluids By Dr. ********************* ******************

2 Introduction base fluid +nano-sized particles (1–100 nm) nanofluid Hence we must use real conditions in our numerical simulations. Introduction Properties 2 Governing equations Lattice Boltzmann method Conclusions

3 Nanofluid properties in modelling Introduction Properties Governing equations Lattice Boltzmann method Conclusions 3

4 viscosity Relation between nanofluid viscosity and basefluid viscosity Arefmanesh and Mahmoodi 2011 Influence of Richardson number and concentration of particles Introduction Properties Governing equations Lattice Boltzmann method Conclusions 4

5 Thermal conductivity Relation between nanofluid thermal conductivity and particle volume fraction Introduction Properties Governing equations Lattice Boltzmann method Conclusions 5

6 Density and heat capacity Pak and Cho correlation: Introduction Properties Governing equations Lattice Boltzmann method Conclusions 6

7 Governing equations IntroductionProperties Governing equations Lattice Boltzmann method Conclusions 7

8 Single-phase modeling Work of Ding and Wen 2005 AuthorsYearGeometryExplanationObservation Lin and Violi 2010 non-uniform particle diameter Enhancement in heat transfer with increase of minimum diameter to maximum diameter ratio Vajjha et al. 2010Complex geometry Augmentation in heat transfer and higher pumping power relative to basefluid IntroductionProperties Governing equations Lattice Boltzmann method Conclusions 8

9 Two-phase modeling The slip velocity between particles and the fluid might not be zero. AuthorsYearGeometryExplanationObservation Behzadmehr et al. 2007 Forced convection of a nanofluid in a tube with uniform heat flux Mixture model Kalte et al.2011Eulerian model More accurate results compared with homogenous models Lotfi et al.2010horizontal tubeComparison Mixture model Eulerian model Single phase model IntroductionProperties Governing equations Lattice Boltzmann method Conclusions 9

10 Lattice Boltzmann method Interface between microscopic and macroscopic point of view (Mesoscopic). AuthorsYearGeometryExplanationObservation Kefayati et al. 2011 Lattice Boltzmann BGK method Good agreement with previous works Lai and Yang2011 Lattice Boltzmann BGK method In high Reynolds number we must use Small size mesh to stability Nabavi et al.2011Multi relaxation time More stability IntroductionProperties Governing equations Lattice Boltzmann method Conclusions 10

11 Conclusions Introduction Properties Governing equations Lattice Boltzmann method Conclusions 11

12 New and future works about nano fluids Non-Newtonian nanofluids Hybrid nanofluids Shafiee Neistanak university of Calgary Suresh research group 12

13 Thanks for your attention. 13


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