Effect of Reynolds Number on Flow past a Square Cylinder in Presence of Upstream and Downstream Flat Plate at Small Gap Spacing

Authors: Shams-ul-Islam, Raheela Manzoor, Zhou Chao Ying

Abstract:

A two-dimensional numerical study for flow past a square cylinder in presence of flat plate both at upstream and downstream position is carried out using the single-relaxation-time lattice Boltzmann method for gap spacing 0.5 and 1. We select Reynolds numbers from 80 to 200. The wake structure mechanism within gap spacing and near wake region, vortex structures around and behind the main square cylinder in presence of flat plate are studied and compared with flow pattern around a single square cylinder. The results are obtained in form of vorticity contour, streamlines, power spectra analysis, time trace analysis of drag and lift coefficients. Four different types of flow patterns were observed in both configurations, named as (i) Quasi steady flow (QSF), (ii) steady flow (SF), (iii) shear layer reattachment (SLR), (iv) single bluff body (SBB). It is observed that upstream flat plate plays a vital role in significant drag reduction. On the other hand, rate of suppression of vortex shedding is high for downstream flat plate case at low Reynolds numbers. The reduction in mean drag force and root mean square value of drag force for upstream flat plate case are89.1% and 86.3% at (Re, g) = (80, 0.5d) and (120, 1d) and reduction for downstream flat plate case for mean drag force and root mean square value of drag force are 11.10% and 97.6% obtained at (180, 1d) and (180, 0.5d).

Keywords: Detached flat plates, drag and lift coefficients, Reynolds numbers, square cylinder, Strouhal number.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1126447

References:

[1] A. Roshko, "On the drag and shedding frequency of two-dimensional bluff bodies," National Advisory Committee for Aeronautics, Technical note no. 3169.
[2] C. J. Apelt, G. S. West and A. A. Szewczyk, "The effects of wake splitter plates on the flow past a circular cylinder in the range 104< R < 5 × 104," Journal of Fluid Mechanics, vol. 61, pp. 187-198, 1973.
[3] C. J. Apelt, G. S. West and A. A. Szewczyk, "The effects of wake splitter plates on the flow past a circular cylinder in the range 104< Re < 5 × 104," Part 2, Journal of Fluid Mechanics, vol. 71, pp. 145-160, 1975.
[4] H. Sakamoto, K. N. TanTakeuchi, and H. Haniu, “Suppression of fluid forces acting on a square prism by passive contro," Journal of Fluids Engineering, vol. 119, pp. 506-511, 1997.
[5] A. Texier, A.S. Cruz Bustamante, L. David, "Contribution of a short separating plate on a control of a swirling process downstream a half-cylinder," Experimental Thermal and Fluid Science, vol. 265, pp. 565-572, 2002.
[6] S. Ozono, "Flow control of vortex shedding by a short splitter plate asymmetrically arranged downstream of a cylinder," Physics of Fluids, vol. 11, pp. 2928-2934.
[7] T. Igarashi, “Drag reduction of a square prism by flow control using a small rod,” Journal of Wind Engineering and Industrial Aerodynamics, vol. 6971, pp.141-153, 1997.
[8] M. Farhadi, K. Sedighi, and E. Fattahi, "Effect of a splitter plate on flow over a semi-circular cylinder," Proceeding of the Institution of Mechanical Engineering, Part G, Journal of Aeroscope Engineering, vol. 224, pp. 321-330, 2010.
[9] K. Kwon, H. Choi, "Control of laminar vortex shedding behind a circular cylinder using splitter plates," Phys, Fluids, vol. 8, pp. 479-486, 1995.
[10] S. Ul. Islam, H. Rahman, W. S. Abbasiand T. Shahina, “Lattice Boltzmann study of wake structure and force statistics for various gap spacings between a square cylinder with a detached flat plate," Arabian Journal for Science and Engineering, vol. 40, pp. 2169-2182, 2015.
[11] S. Turki, "Numerical simulation of passive control on vortex shedding behind square cylinder using splitter plate," Engineering Applications of Computational Fluid Mechanics, vol. 2, pp. 514-524, 2008.
[12] S. Ul. Islam, H. Rahman, W. S. Abbasi, U. Noreen and A. Khan, "Suppression of fluid force on flow past a square cylinder with a detached flat plate at low Reynolds number for various spacing ratios, Journal of Mechanical Science and Technology, vol. 28, pp. 4969-4978, 2014.
[13] M. Md. Alam, M. Moriya, K. Takai, and H. Sakamoto, “Suppression of fluid forces acting on two square prisms in a tandem arrangement by passive control of flow," Journal of Fluids and Structures, vol. 16, pp. 1073-1092, 2002.
[14] L. Zhou, M. Cheng, and K.C. Hung, “Suppression of fluid force on a square cylinder by flow control," Journal of Fluids and Structures, vol. 21, pp. 151-167.
[15] M. S. M. Ali, C. J. Doolan and V. Wheatley, "Low Reynolds number flow over a square cylinder with a detached flat plate," International journal of Heat and Fluid Flows, vol. 36, pp. 133-141, 2012.
[16] S. Malekzadeh and A. Sohankar, "Reduction of fluid forces and heat transfer on a square cylinder in a laminar flow regime using a control plate," International Journal of Heat and Fluid Flow, vol. 34, pp. 15-27, 2012.
[17] A. Gupta, “Suppression of vortex shedding in a flow around square cylinder using control plate,” pp. 1-13, 2013 (home.iitk.ac.in/~gabhinav/Abhinav_Gupta_paper.pdf).
[18] J. Hwang, K. Yang, S. Sun, "Reduction of flow induced forces on a circular cylinder using a detached splitter plate," Phys. Fluids, vol. 15, pp. 2433-2436, 2003.
[19] L. Liu, M. Liu, B. Teng, Z. D. Cui, G. Q. Tang, M. Zhao and L. Cheng, "Numerical investigation of fluid flow past circular cylinder with multiple control rods at low Reynolds number," Journal of Fluids and Structures. vol. 48, pp. 235-259, 2014.
[20] G. R. Vamsee., M. L. De Tena and S. Tiwari, "Effect of arrangement of inline splitter plate on flow past square cylinder," Progress in Computational Fluid Dynamics. vol. 14, pp. 277-293, 2014.
[21] M. Breuer, J. Bernsdorf, T.Zeifer and F. Durst, " Accurate computations of the laminar flow past a square cylinder based on two different methods: Lattice-Boltzmann and finite-volume," Journal of Heat and Fluid Flows, vol. 21. pp. 186-196, 2000.
[22] C. J. Doolan, "Bluff body noise reduction using aerodynamic interference," in Australian Institute of Physics (AIP), 18th National Congress, Adelaids, South Australia, 2008.
[23] A. Sohanker, C. Norberg and L. Davidson, "Simulation of three dimensional flow around a square cylinder at moderate Reynolds number," Physics of fluids, Vol. 11, no. 2, pp. 288-306, 1999.
[24] A. K. Saha, G. Biswas and K. Muralidha, "Three-dimensional study of flow past a square cylinder at low Reynolds number," International journal of Heat and Fluid Flow, Vol. 24, no.1, pp. 54-66, 2003.
[25] Z. Guo, H. Liu, LI. S. Luo and K. Xu," A comparative study of the LBE and GKS methods for 2D near incompressible laminar flows," Journal of Computational Physics, Vol. 227, pp. 4955-4976, 2008.
[26] M. Breuer, J. Bernsdorf, T.Zeifer and F. Durst, " Accurate computations of the laminar flow past a square cylinder based on two different methods: Lattice-Boltzmann and finite-volume," Journal of Heat and Fluid Flows, Vol. 21. pp. 186-196, 2000.
[27] Y. Dazh, M. Renwei, L.S. Luo, and S. Wei, “Viscous flow computations with the method of lattice Boltzmann equation”, Progress in Aerospace Sciences, Vol. 39, pp. 329-367,2003.
[28] S. Ul. Islam, W. S. Abbasi, and C. Y. Zhou, “Transitions in the unsteady wakes and aerodynamic characteristics of the flow past three square cylinders aligned inline”, Aerospace Science and Technology, Vol. 50, pp. 96-111,2016.
[29] S. Ul. Islam, C. Y. Zhou, A. Shah, and P. Xie, “Numerical simulation of flow past rectangular cylinders with different aspect ratios using the incompressible lattice Boltzmann method”, Journal of Mechanical Science and Technology, Vol. 26, pp. 1027-1041, 2012.
[30] S. Ul. Islam, H. Rahman, C. Y. Zhou, and S. C. Saha, “Comparison of wake structures and force measurements behind three side-by-side cylinders”, Journal of the Brazilian Society of Mechanical Science and Engineering, DOI 10.1007/s40430-014-0297x.
[31] S. Ul. Islam, W. S. Abbasi, H. Rahman, and R. Naheed, “Numerical investigation of wake modes for flow past three tandem cylinders using the multi-relaxation-time lattice Boltzmann method for different gap spacings”, Journal of the Brazilian Society of Mechanical Science and Engineering, DOI 10.1007/s40430-014-0282-4.
[32] S. Ul. Islam, W. S. Abbasi, and A. Khan, “The effect of Reynolds numbers for unequal gap spacings on flow past three square cylinders arranged in-line”, Journal of the Brazilian Society of Mechanical Science and Engineering, DOI 10.1007/s40430-015-0468-4.
[33] H. Rahman, S. Ul. Islam, C. Y. Zhou, T. Kiyani, and S. C. Saha, “On the effect of Reynolds number for flow past three side-by-side square cylinders for unequal gap spacings”, KSCE Journal of Civil Engineering, Vol. 19, pp. 233-247, 2015.
[34] W. S. Abbasi, S. Ul. Islam, S. C. Saha, Y. T. Gu, and C. Y. Zhou, “Effect of Reynolds numbers on flow past four square cylinders in an in-line square configuration for different gap spacings”, Journal of Mechanical Science and Technology, Vol. 28, pp. 539-552, 2014.