Heat Transfer To Laminar Flow Over A Double Backward-Facing Step

• Main Authors: Togun, Hussein, Tuqa Abdulrazzaq, S. N. Kazi, A. Badarudin, M. K. A. Ariffin
• Format: Text
• Language: English
• Published: Zenodo 2013
• Subjects: Laminar flow; Double backward; Separation flow; Recirculation flow.; Chiang; tylli
• Online Access: https://dx.doi.org/10.5281/zenodo.1087932; https://zenodo.org/record/1087932

Heat transfer and laminar air flow over a double backward-facing step numerically studied in this paper. The simulations was performed by using ANSYS ICEM for meshing process and using ANSYS fluent 14 (CFD) for solving. The k-ɛ standard model adopted with Reynolds number varied between 98.5 to 512 and three step height at constant heat flux (q=2000 W/m2). The top of wall and bottom of upstream are insulated with bottom of downstream is heated. The results show increase in Nusselt number with increases of Reynolds number for all cases and the maximum of Nusselt number happens at the first step in compared to the second step. Due to increase of cross section area of downstream to generate sudden expansion then Nusselt number decrease but the profile of Nusselt number keep same trend for all cases where increase after the first and second steps. Recirculation region after the first and second steps are denoted by contour of streamline velocity. The higher augmentation of heat transfer rate observed for case 1 at Reynolds number of 512 and heat flux q=2000 W/m 2 . : {"references": ["D.E. Abbot, Kline, S.J., , Experimental investigations of subsonic\nturbulent flow over single and double backward-facing steps, Trans.\nA.S.M.E. D: J. Basic Eng., 84 (1962) 317\u2013325.", "R.J. Goldstein, Eriksen, V.L., Olson, R.M., Eckert, E.R.G, Laminar\nseparation reattachment, and transition of flow over a downstreamfacing\nstep. , Trans. ASME. D: J. Basic Eng. , 92 (1970) 732\u2013741.", "B.F. Armaly, F. Durst, J.C.F. Pereira, B. Sch\u00f6nung, Experimental and\ntheoretical investigation of backward-facing step flow, Journal of Fluid\nMechanics, 127 (1983) 473-496.", "H.I. Abu-Mulaweh, A review of research on laminar mixed convection\nflow over backward- and forward-facing steps, International Journal of\nThermal Sciences, 42(9) (2003) 897-909..", "D. Barkley, M.G.M. Gomes, R.D. Henderson, Three-dimensional\ninstability in flow over a backward-facing step, Journal of Fluid\nMechanics, 473 (2002) 167-190.", "S. Terhaar, A. Velazquez, J.R. Arias, M. Sanchez-Sanz, Experimental\nstudy on the unsteady laminar heat transfer downstream of a backwards\nfacing step, International Communications in Heat and Mass Transfer,\n37(5) (2010) 457-462.", "K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting\nfluid flow and heat transfer in separating and reattaching flows\u2014I. Flow\nfield calculations, International Journal of Heat and Mass Transfer, 37(1)\n(1994) 139-151.", "K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting\nfluid flow and heat transfer in separating and reattaching flows\u2014II.\nThermal field calculations, International Journal of Heat and Mass\nTransfer, 38(8) (1995) 1467-1481.", "J.C. Vogel, Heat Transfer and Fluid Mechanics Measurements in the\nTurbulent Reattaching Flow Behind a Backward-facing Step, Stanford\nUniversity, 1984.\n[10] T. P. Chiang and Tony W. H. Sheu, A numerical revisit of backwardfacing\nstep flow problem Journal of Phys. Fluids 11 (1999) 862-875.\n[11] N. Tylli, L. Kaiktsis, B. Ineichen, Sidewall effects in flow over a\nbackward-facing step: Experiments and numerical simulations, Physics\nof Fluids, 14(11) (2002) 3835-3845.\n[12] F. Durst and J. C. F. Pereira, Time dependent laminar backward facing\nstep flow in a two dimensional duct, J. Fluid Eng. , 110 (1988) 289-296.\n[13] M.B. G. Biswas, F. Durst, Backward-facing step flows for various\nexpansion ratios at low and moderate Reynolds number, Journal of\nFluids Engineering, 126 (2004 ) 362-374.\n[14] C.E. Tinney, L.S. Ukeiley, A study of a 3-D double backward-facing\nstep, Exp Fluids, 47(3) (2009) 427-438.\n[15] B.F. Armaly, A. Li, J.H. Nie, Measurements in three-dimensional\nlaminar separated flow, International Journal of Heat and Mass Transfer,\n46(19) (2003) 3573-3582."]}