Heat Transfer to Laminar Flow over a Double Backward-Facing Step
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/m2.
[1] D.E. Abbot, Kline, S.J., , Experimental investigations of subsonic
turbulent flow over single and double backward-facing steps, Trans.
A.S.M.E. D: J. Basic Eng., 84 (1962) 317–325.
[2] R.J. Goldstein, Eriksen, V.L., Olson, R.M., Eckert, E.R.G, Laminar
separation reattachment, and transition of flow over a downstreamfacing
step. , Trans. ASME. D: J. Basic Eng. , 92 (1970) 732–741.
[3] B.F. Armaly, F. Durst, J.C.F. Pereira, B. Schönung, Experimental and
theoretical investigation of backward-facing step flow, Journal of Fluid
Mechanics, 127 (1983) 473-496.
[4] H.I. Abu-Mulaweh, A review of research on laminar mixed convection
flow over backward- and forward-facing steps, International Journal of
Thermal Sciences, 42(9) (2003) 897-909..
[5] D. Barkley, M.G.M. Gomes, R.D. Henderson, Three-dimensional
instability in flow over a backward-facing step, Journal of Fluid
Mechanics, 473 (2002) 167-190.
[6] S. Terhaar, A. Velazquez, J.R. Arias, M. Sanchez-Sanz, Experimental
study on the unsteady laminar heat transfer downstream of a backwards
facing step, International Communications in Heat and Mass Transfer,
37(5) (2010) 457-462.
[7] K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting
fluid flow and heat transfer in separating and reattaching flows—I. Flow
field calculations, International Journal of Heat and Mass Transfer, 37(1)
(1994) 139-151.
[8] K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting
fluid flow and heat transfer in separating and reattaching flows—II.
Thermal field calculations, International Journal of Heat and Mass
Transfer, 38(8) (1995) 1467-1481.
[9] J.C. Vogel, Heat Transfer and Fluid Mechanics Measurements in the
Turbulent Reattaching Flow Behind a Backward-facing Step, Stanford
University, 1984.
[10] T. P. Chiang and Tony W. H. Sheu, A numerical revisit of backwardfacing
step flow problem Journal of Phys. Fluids 11 (1999) 862-875.
[11] N. Tylli, L. Kaiktsis, B. Ineichen, Sidewall effects in flow over a
backward-facing step: Experiments and numerical simulations, Physics
of Fluids, 14(11) (2002) 3835-3845.
[12] F. Durst and J. C. F. Pereira, Time dependent laminar backward facing
step flow in a two dimensional duct, J. Fluid Eng. , 110 (1988) 289-296.
[13] M.B. G. Biswas, F. Durst, Backward-facing step flows for various
expansion ratios at low and moderate Reynolds number, Journal of
Fluids Engineering, 126 (2004 ) 362-374.
[14] C.E. Tinney, L.S. Ukeiley, A study of a 3-D double backward-facing
step, Exp Fluids, 47(3) (2009) 427-438.
[15] B.F. Armaly, A. Li, J.H. Nie, Measurements in three-dimensional
laminar separated flow, International Journal of Heat and Mass Transfer,
46(19) (2003) 3573-3582.
[1] D.E. Abbot, Kline, S.J., , Experimental investigations of subsonic
turbulent flow over single and double backward-facing steps, Trans.
A.S.M.E. D: J. Basic Eng., 84 (1962) 317–325.
[2] R.J. Goldstein, Eriksen, V.L., Olson, R.M., Eckert, E.R.G, Laminar
separation reattachment, and transition of flow over a downstreamfacing
step. , Trans. ASME. D: J. Basic Eng. , 92 (1970) 732–741.
[3] B.F. Armaly, F. Durst, J.C.F. Pereira, B. Schönung, Experimental and
theoretical investigation of backward-facing step flow, Journal of Fluid
Mechanics, 127 (1983) 473-496.
[4] H.I. Abu-Mulaweh, A review of research on laminar mixed convection
flow over backward- and forward-facing steps, International Journal of
Thermal Sciences, 42(9) (2003) 897-909..
[5] D. Barkley, M.G.M. Gomes, R.D. Henderson, Three-dimensional
instability in flow over a backward-facing step, Journal of Fluid
Mechanics, 473 (2002) 167-190.
[6] S. Terhaar, A. Velazquez, J.R. Arias, M. Sanchez-Sanz, Experimental
study on the unsteady laminar heat transfer downstream of a backwards
facing step, International Communications in Heat and Mass Transfer,
37(5) (2010) 457-462.
[7] K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting
fluid flow and heat transfer in separating and reattaching flows—I. Flow
field calculations, International Journal of Heat and Mass Transfer, 37(1)
(1994) 139-151.
[8] K. Abe, T. Kondoh, Y. Nagano, A new turbulence model for predicting
fluid flow and heat transfer in separating and reattaching flows—II.
Thermal field calculations, International Journal of Heat and Mass
Transfer, 38(8) (1995) 1467-1481.
[9] J.C. Vogel, Heat Transfer and Fluid Mechanics Measurements in the
Turbulent Reattaching Flow Behind a Backward-facing Step, Stanford
University, 1984.
[10] T. P. Chiang and Tony W. H. Sheu, A numerical revisit of backwardfacing
step flow problem Journal of Phys. Fluids 11 (1999) 862-875.
[11] N. Tylli, L. Kaiktsis, B. Ineichen, Sidewall effects in flow over a
backward-facing step: Experiments and numerical simulations, Physics
of Fluids, 14(11) (2002) 3835-3845.
[12] F. Durst and J. C. F. Pereira, Time dependent laminar backward facing
step flow in a two dimensional duct, J. Fluid Eng. , 110 (1988) 289-296.
[13] M.B. G. Biswas, F. Durst, Backward-facing step flows for various
expansion ratios at low and moderate Reynolds number, Journal of
Fluids Engineering, 126 (2004 ) 362-374.
[14] C.E. Tinney, L.S. Ukeiley, A study of a 3-D double backward-facing
step, Exp Fluids, 47(3) (2009) 427-438.
[15] B.F. Armaly, A. Li, J.H. Nie, Measurements in three-dimensional
laminar separated flow, International Journal of Heat and Mass Transfer,
46(19) (2003) 3573-3582.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:65155", author = "Hussein Togun and Tuqa Abdulrazzaq and S. N. Kazi and A. Badarudin and M. K. A. Ariffin", title = "Heat Transfer to Laminar Flow over a Double Backward-Facing Step ", abstract = "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/m2.
", keywords = "Laminar flow, Double backward, Separation flow, Recirculation flow.", volume = "7", number = "8", pages = "1742-6", }
