Keywords: simulation, one-line cylinders, ANSYS, turbulent flow, vortex patterns


In this work, a numerical simulation using Computation Fluid Dynamics technique was used to investigate the flow properties and turbulence characteristics through flow of one-line cylinder in an open channel with uniform flow conditions. A two-dimensional turbulence model was applied using ANSYS. Flow properties were investigated against varying cylinder diameters that forms a one-line cylinder physical model and varying flow rates. Three cylinders diameters D were used (5.0 cm, 2.5 cm and 1.25 cm) and located at 12.5 cm apart along the flume centre-line. Spatial distributions of mean-stream-wise velocity, pressure, turbulent kinetic energy, and eddy viscosity were estimated. Results showed symmetrical distribution of flow velocity, turbulence eddy, and turbulent kinetic energy along the one-line cylinder for the largest cylinder diameter. Vortex shedding patterns were well predicted by the numerical simulation behind the cylinders. Different configurations of vortices distribution behind the cylinders were recorded for the diameters of 1.25 cm and 2.5 cm. The flow pattern difference between the largest diameter (5 cm) and the small diameters (2.5 cm and 1.25 cm) was leaded to the strong overlap for the vortices in the wake for the lined cylinders with the large diameter in comparison to the other diameters. Consequently, this study is investigated the different diameter sizes of a one-line cylinder with the same spacing between them on the flow pattern along the channel.


Niemann, H. J., & Holscher, N. (1990). A review of recent experiments on flow past circular cylinders. Journal of Wind Engineering and Industrial Aerodynamics, 33(1-2), 197-209,>

Mulahasan S., Stoesser T. and McSherry R. (2017). Effect of floodplain obstructions on the discharge conveyance capacity of compound channels. Journal of Irrigation and Drainage Engineering, 2017, 143(11),>

Mulahasan S. (2017). Effect of sidewall proximity on the flow around a circular cylinder. 4th International Symposium on Shallow Flows. Eindhoven University of Technology, NL, 26-28 June.

Zdravkovich, M. M. (1987). The effects of interference between circular cylinders in cross flow. Journal of Fluids and Structures, 1(2), 239-261,

Papaioannou, G. V., Yue, D. K., Triantafyllou, M. S., and Karniadakis, G. E.  (2006). Three-dimensionality effects in flow around two tandem cylinders. Journal of Fluid Mechanics, 558, pp. 387–413. 10.1017/S0022112006000139.

Lockard, D., Choudhari, M., Khorrami, M., Neuhart, D., Hutcheson, F., Brooks, T., and Stead, D. (2008). Aeroacoustic simulations of tandem cylinders with subcritical spacing. In 14th AIAA/CEAS Aeroacoustics Conference (29th AIAA Aeroacoustics Conference)

Palau-Salvador, G., Stoesser, T. and Rodi, W. (2008). LES of the flow around two cylinders in tandem'' Journal of Fluids and Structures, 24(8), 1304-1312

Zdravkovich, M. M (1997). Flow around circular cylinders. Volume 2: Applications (Vol 2). Oxford University Press.

Aiba, S. and Yamazaki, Y. (1976). An Experimental investigation of heat transfer around a tube in a bank', Journal of Heat Transfer, 98(3), 503-512,>

Igarashi, T. & Suzuki, K. (1984). Characteristics of the flow around three circular cylinders. Bulletin of Japan Socity of Mechanical Engineering, 27, 2397-2404, quoted in M. M. Zdravkovich, Flow around circular cylinders. Volume 2: Applications, 1080,>

Igarashi, T (1986). Characteristics of the flow around four circular cylinders arranged in- line. Bulletin of Japan Society of Mechanical Engineers, 29, 751-7. Quoted in M.M. Zdravkovich, Flow around circular cylinders Volume 2: Applications, 1097,>

Crowdy, D. G. (2006). Analytical solutions for uniform potential flow past multiple cylinders. European Journal of Mechanics B/Fluids, 25, 459–470.

Fornarelli, F., Oresta, P. and Lippolis, A. (2014). Flow patterns and heat transfer around six in-line circular cylinders at low Reynolds number,>

Fornarelli, F., Lippolis, A. and Oresta, P. (2016) Buoyancy induced transitions on heat and mass transfer around multiple bluff bodies. Journal of Heat Transfer, 139 (2),

Liang C., Papadakis, G., Luo, X. (2009). Effect of tube spacing on the vortex shedding characteristics of laminar flow past an inline tube array: A numerical study. Computers & Fluids, 38, 950–964,>

Mulahasan S. & Stoesser T. (2015).  Flow resistance of in-line vegetation in open channel flow. International Journal of River Basin Management,>

Yokojima, S., Asaoka, R., Yoshino, K., Noda, H. & Miyahara, T. (2017). On permeability and roughness effects in flow past a row of circular cylinders arranged along the centerline of a straight flume. Proceedings of the 37th IAHR World Congress August 13 – 18, 2017, Kuala Lumpur, Malaysia.

Sun, X., and Shiono, K. (2009). Flow resistance of one-line emergent vegetation along the floodplain edge of a compound open channel. Advances in Water Resources, 32, 430–438,

Terrier, B. (2010) Flow characteristics in straight compound channels with vegetation along the main 567 channel, Dessertation presented to Department of Civil and Building Engineering 568Loughborough University.

Goliatt, L., Sulaiman, S. O., Khedher, K. M., Aitazaz Ahsan Farooque, A. A., and Yaseen. Z. M. (2021). Estimation of natural streams longitudinal dispersion coefficient using hybrid evolutionary machine learning model. Engineering Applications of Computation Fluid Mechanics, 15, 1298-1320,

Zhao, M., Kaja, K., Xiang, Y., and Cheng, L. (2016). Vortex-induced vibration of four cylinders in an in-line square configuration. Physics of Fluids, 28, 023602,>

Gubashi, K. R., Mulahasan, S., Jameel, M. A., and Al-Madhhachi, A. S. T. (2022).  Evaluation drag coefficients for circular patch vegetation with different riverbed roughness. Cogent Engineering, 9 (1), 2044574,

Salvador, G. P., Stoesser, T., Fröhlich, J., and Wolfgang Rodi, W. (2008). LES of the flow around two cylinders in tandem, Journal of Fluids and Structures, 24 (8), 1304-1312," target="_blank" rel="noopener"> class="MsoHyperlink">.

Hamed, A.M., Peterlein, A. M., and Randle, L. V. (2019). Turbulent boundary layer perturbation by two wall-mounted cylindrical roughness elements arranged in tandem: Effects of spacing and height ratio, Physics of Fluids 31, 065110;

Keshvarzi, A., Shrestha, C. K., Zahedani, M. R., Ball, J., & Khabbaz, H. (2018). Experimental study of flow structure around two in-line bridge piers. In Proceedings of institution of civil engineers-water management 171, (6), 311-327. Thomas Telford Ltd.

Al-Hashimi, S. AM., Saeed, K. A., and Nahi, T. (2019). Experimental and CFD Modeling of Hydraulic Jumps Forming at Submerged Weir. Journal of The Institution of Engineers (India) Series A, (100), 487-493,                     >

Launder, B. E. and Sharma, B. I. (1974). Application of the energy dissipation model of turbulence to the calculation of flow near a spinning disc. Letter in Heat and Mass Transfer, 1 (2), 131-137.

Wilcox, D.C. (1998). Turbulence Modeling for CFD. 2nd Edition, DCW Industries, La Canada, California.

Launder, B.E. and Spalding, D.B. (1974). The Numerical computation of turbulent flows. Computer Methods in Applied Mechanics and Engineering, 3, 269-289,>

Sumner, D., Richards, MD., Akosile, OO. (2005). Two staggered circular cylinders of equal diameter in cross flow.  Journal of Fluids and Structures, 20, 255-276,>

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