Tham khảo tài liệu 'heat transfer mathematical modelling numerical methods and information technology part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Fast BEM Based Methods for Heat Transfer Simulation 229 A hotstrip in a cavity produces two vortices one on each side. For Ra 105 the flow field is symmetric in the case of central placement of the hotstrip. Symmetry is lost when hotstrip is place off-centre. Most of the heat is transferred from the sides of the hotstrip and only a small part from the top wall. Introduction of nanofluids leads to enhanced heat transfer in all cases. The enhancement is largest when conduction is the dominant heat transfer mechanism since in this case the increased heat conductivity of the nanofluid is important. On the other hand in convection dominated flows heat transfer enhancement is smaller. All considered nanofluids enhance heat transfer for approximately the same order of magnitude Cu nanofluid yielding the highest values. Heat transfer enhancement grows with increasing solid particle volume fraction in the nanofluid. The differences between temperature fields when using different nanofluids with the same solid nanoparticle volume fraction are small. In future the proposed method for simulating fluid flow and heat transfer will be expanded for simulation of unsteady phenomena and turbulence. 6. References Abu-Nada E. 2008 . Application of nanofluids for heat transfer enhancement of separated flows encountered in a backward facing step Int. J. Heat Fluid Fl. 29 242-249. Abu-Nada E. Oztop H. F 2009 . Effects of inclination angle on natural convection in enclosures filled with cuwater nanofluid Int. J. Heat Fluid Fl. 30 669-678. Akbarinia A. Behzadmehr A. 2007 . Numerical study of laminar mixed convection of a nanofluid in horizontal curved tubes Applied Thermal Engineering 27 1327-1337. Bebendorf M. 2000 . Approximation of boundary element matrices Numer. Math 86 565-589. Bebendorf M. Rjasanow S. 2003 . Adaptive low rank approximation of collocation matrices Computing 70 1-24. Brinkman H. C. 1952 . The viscosity of concentrated suspensions and solutions J. Chem. Phys. 20 .
