Abstract
Here we investigate fluid flow in 90-degree bends with and without orifice-like constrictions. The results of flow in non-constricted bends were compared with experimental results for similar Reynolds numbers and found to be in good agreement. Calculations were then carried out for various Reynolds numbers in the laminar and turbulent regimes. In addition, constrictions up to a 60% blockage were incorporated. The present study shows that the Reynolds number and the presence of an orifice-like constriction affects the velocity profile and the pressure distribution. The results indicate that if a sudden contraction is encountered, the peak velocity is larger and the flow is more predisposed to the outer wall than it otherwise would be. In addition, a sudden contraction increases the pressure loss compared to the constant-area bend and it affects the pressure distribution throughout the entire bend. This paper provides a means to predict pressure losses (similar to minor loss coefficients) in rounded bends in the presence or absence of constrictions. Such information is important to practicing engineers for designing fluid-flow conveyance systems. The behavior of the fluid is shown to be connected to the constriction and is also affected by the Reynolds number.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Abraham, J. P., Sparrow, E. M., Tong J. C. K., and Bettenhausen, D. W. (2010). “Internal flows which transist from turbulent through intermittent to laminar.” Int. J. Thermal Sciences, Vol. 49, No. 2, pp. 256–263.
Abraham, J. P., Sparrow, E. M., and Minkowycz, W. J. (2011). “Internalflow Nusselt numbers for the low-Reynolds number end of the laminar-to-turbulent transition regime.” Int. J. Heat Mass Transfer, Vol. 54, Nos. 1–3, pp. 584–588.
Abraham, J. P., Tong, J. C. K., and Sparrow, E. M. (2008). “Breakdown of laminar pipe flow into transitional intermittency and subsequent attainment of fully developed intermittent or turbulent flow.” Num. Heat Transfer B, Vol. 54, No. 2, pp. 103–115.
Abraham, J. P., Tong, J. C. K., and Sparrow, E. M. (2009). “Heat transfer in all pipe flow regimes–laminar, transitional/intermittent, and turbulent.” Int. J. Heat Mass Transfer, Vol. 52, Nos. 3–4, pp. 557–563.
Acheson, D. J. (1990). Elementary Fluid Dynamics, Oxford Applied Mathematics and Computing Science Series. New York: Oxford University Press.
Al-Qahtani, M., Jang, Y., Chen, H., and Han, J. (2002). “Flow and heat transfer in rotating two-pass rectangular Channels (AR=2) by Reynolds stress turbulence model.” Int. J. Heat Mass Transfer., Vol. 45, No. 9, pp. 1823–1838.
Bansal, P. K. and Wang, G. (2004). “Numerical analysis of choked refrigerant flow in adiabatic capillary tubes.” Appl. Therm. Eng., Vol. 24, Nos. 5–6, pp. 851–863.
Batchelor, G. K. (1967). An Introduction to Fluid Dynamics, London: Cambridge University Press.
Bengoechea, A., Anton, R., Larraona, G. S., Ramos, J. C., and Rivas, A. (2014) “Influence of geometrical parameters on downstream flow of a screen under fan-induced swirl.” Conditions Eng. Appl. Comp. Fluid Mech., Vol. 8, No. 4, pp. 623–638.
Bovendeerd, P. H. M., Steenhoven, A. A. V., Vosse, F. N. V. D., and Vossers, G. (1987). “Steady entry flow in a curved pipe.” J. Fluid Mech., Vol. 177, pp. 233–246.
Bui, V. A. (2008) “Simplified turbulence models for confined swirling flows.” Eng. Appl. Comp. Fluid Mech., Vol. 2, No. 4, pp. 404–410.
Crane (1999). “Flow of Fluids Through Valves, Fittings, and Pipes.” Crane Valves North American, Technical Paper No. 410M, 1999.
Daneshfaraz, R. (2013). “3-D Investigation of velocity profile and pressure distribution in bends with different diversion angle.” Journal. Civil Eng. Sci., Vol. 2, No. 4, pp. 234–240.
Galvan, S., Reggio, M., and Francois, G. (2011). “Assessment study of k-e turbulence models and near-wall modeling for steady state swirl analysis in drift tube using Fluid.” Eng. Appl. Comp. Fluid Mech., Vol. 5, No. 4, pp. 459–478.
Gorman, J. M., Sparrow, E. M., Mowry, G. S., and Abraham, J. P. (2011). “Simulation of helically wrapped, compact heat exchangers.” J. Renew. Sustain. Energy, 3, article no. 043120.
Kamel, B., Kriba, I., Ali, F., and Abdelbaki, D. (2014). “3D simulation of velocity profile of turbulent flow in open channel with complex geometry.” Phys. Procedia., Vol. 55, No. 1, pp. 119–128.
Kays, W. M. and Crawford, M. E. (1993). Convective Heat and Mass Transfer, McGraw-Hill, New York.
Koutsou, C. P., Yiantsios, S. G., and Karabelas, A. J. (2007). “Direct numerical simulation of flow in spacer-filled channels: Effect of spacer geometrical characteristics.” J. Membrane. Sci., Vol. 291, Nos. 1–2, pp. 53–69.
Launder, B. E. and Spalding, D. B. (1974). “The numerical computation of turbulent flows.” Comp. Method. Appl. Mech. Eng., Vol. 3, No. 2, pp. 269–289.
Manzar, M. A. and Shah, S. N. (2009). “Particle distribution and erosion during the flow of Newtonian and non-Newtonian slurries in straight and coiled pipes.” Eng. Appl. Comp. Fluid Mech., Vol. 3, No. 3, pp. 296–320.
Messa, G. V. and Malavasi, S. (2014). “Numerical prediction of particle distribution of solid-liquid slurries in straight pipes and bends.” Eng. Appl. Comp Fluid Mech., Vol. 8, No. 3, pp. 356–372.
Morrissey, M. M. and Chouet, B. A. (1997). “A numerical investigation of choked flow dynamics and its application to the triggering mechanism of long-period events at Redoubt Volcano, Alaska.” J. Geophys. Res., Vol. 102, No. B4, pp. 7965–7983.
Nakayama, H., Hirota, M., Fujita, H., Yamada, T., and Koide, Y. (2003). “Flow characteristics in rectangular ducts with a sharp 180-degree turn.” JSME, Vol. 2, No. 1028, pp. 1171–1179.
Olson D. E. (1971). Fluid mechanics relevant to respiration: Flow within curved or elliptical tubes and bifurcating systems, Ph.D. Thesis, University of London.
Rend, R. R., Sparrow, E. M., Bettenhausen, D. W., and Abraham, J. P. (2013). “Parasitic pressure losses in diffusers and in their downstream piping systems for fluid flow and heat transfer.” International Journal of Heat and Mass Transfer, Vol. 61, No. 1, pp. 56–61.
Sadeghfam, S. and Akhtari, A. A. (2012). “Numerical investigation of length and thickness of separation zone after sudden change of direction in closed Sections.” Journal. Civil Eng. Urban., Vol. 2, No. 1, 35–39.
Sanchez-Silva, F., Gomer, A., Toledo, M., Quinto, P., and Zurita, V. (2003). “Experimental and numerical curved flow study for metrology purposes.” J. Appl. Res. Tech., Vol. 1, No. 2, pp. 114–126.
Sarkardeh, H., Zarrati, A.R., Jabbari, E., and Marosi, M. (2014). “Numerical simulation and analysis of flow in a reservoir in the presence of vortex.” Eng. Appl. Comp. Fluid Mech., Vol. 8, No. 4, pp. 598–608.
Shokouhmand, H. and Zareh, M. (2014). “Experimental investigation and numerical simulation of choked refrigerant flow through helical adiabatic capillary tube.” Appl. Therm. Eng., Vol. 63, No. 1, pp. 119–128.
Sparrow, E. M., Abraham, J. P., and Minkowycz, W. J. (2009). “Flow separation in a diverging conical duct: Effect of Reynolds number and divergence angle.” Int. J. Heat Mass Transfer, Vol. 52, Nos. 13–14, pp. 3079–3083.
Van De Vosse, F. N., Van Steenhoven, A. A., Segal, A., and Janseen, J. D. (1989). “A finite element analysis of steady laminar entrance flow in a 90 Curved tube.” Int. J. Numer. Meth. F., Vol. 9, No. 3, pp. 275–287.
Yakhot, V., Orszag, S. A., Thangam, S., Gatski, T. B., and Speziale, C. G. (1992). “Development of turbulence models for shear flows by a double expansion technique.” Phys. Fluids A, Vol. 4, No. 7, pp. 1510–1520.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Daneshfaraz, R., Rezazadehjoudi, A. & Abraham, J. Numerical investigation on the effect of sudden contraction on flow behavior in a 90-degree bend. KSCE J Civ Eng 22, 603–612 (2018). https://doi.org/10.1007/s12205-017-1313-3
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12205-017-1313-3