[en] This paper presents the results of investigations into the flow around a rectangular cylinder with a chord-to-depth ratio equal to 4. The studies are performed through wind tunnel dynamic pressure measurements along a cross section combined with two-dimensional Unsteady Reynolds-Averaged Navier-Stokes (URANS) and three-dimensional Delayed-Detached Eddy Simulation (DDES). These experimental and numerical studies are complementary and combining them allows a better understanding of the unsteady dynamics of the flow. These studies aim mainly at determining the effects of the rectangle incidence and freestream velocity on the variation of the flow topology and the aerodynamic loads, and at assessing the capability of the industrially affordable URANS and DDES approaches to provide a sufficiently accurate estimation of the flow for different incidences. The comparison of experimental and numerical data is performed using statistics and Dynamic Mode Decomposition. It is shown that the rectangular cylinder involves complex separation-reattachment phenomena that are highly sensitive to the Reynolds number. In particular, the time-averaged lift slope increases rapidly with the Reynolds number in the range 7.8e3 < Re < 1.9e4 due to the modification of the time-averaged vortex strength, thickness and distance from the surface. Additionally, it is shown that both URANS and DDES simulations fail to accurately predict the flow at all the different incidence angles considered. The URANS approach is able to qualitatively estimate the spatio-temporal variations of vortices for incidences below the stall angle alpha = 4°. Nonetheless, URANS does not predict stall, while DDES correctly identifies the stall angle observed experimentally.
Guissart, Amandine ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Modélisation et contrôle des écoulements turbulents
Andrianne, Thomas ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale
Dimitriadis, Grigorios ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Interactions Fluide-Structure - Aérodynamique expérimentale
Terrapon, Vincent ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Modélisation et contrôle des écoulements turbulents
Language :
English
Title :
Numerical and experimental study of the flow around a 4:1 rectangular cylinder at moderate Reynolds number
Publication date :
June 2019
Journal title :
Journal of Wind Engineering and Industrial Aerodynamics
Bartoli, G., Borsani, A., Mannini, C., Marra, A., Procino, L., Ricciardelli, F., Wind tunnel study on the aerodynamics of a 5:1 rectangular cylinder in smooth flow. Proceedings of the Thirteenth International Conference on Wind Engineering, 2011 (Amsterdam, The Netherlands).
Bartoli, G., Bruno, L., Buresti, G., Ricciardelli, F., Salvetti, M., Zasso, A., BARC Overview Document. 2008.
Bergh, H., Tijdeman, H., Theoretical and experimental results for the dynamic response of pressure measuring systems. Nation. Lucht-en Ruimtevaartlaboratorium, 1965 Technical Report, NLR-TR F.238.
Bruno, L., Coste, N., Fransos, D., Simulated flow around a rectangular 5:1 cylinder: spanwise discretisation effects and emerging flow features. J. Wind Eng. Ind. Aerod. 104–106 (2012), 203–215.
Bruno, L., Fransos, D., Coste, N., Bosco, A., 3D flow around a rectangular cylinder: a computational study. J. Wind Eng. Ind. Aerod. 98 (2010), 263–276.
Bruno, L., Salvetti, M.V., ERCOFTAC QNET-CFD Knowledge Base Wiki: Benchmark on the Aerodynamics of a Rectangular 5:1 Cylinder (BARC). 2017 http://www.kbwiki.ercoftac.org/w/index.php/Abstr:UFR_2-15. (Accessed 27 November 2018)
Bruno, L., Salvetti, M.V., Ricciardelli, F., Benchmark on the aerodynamics of a rectangular 5:1 cylinder: an overview after the first four years of activity. J. Wind Eng. Ind. Aerod. 126 (2014), 87–106.
Carassale, L., Freda, A., Marr-Brunenghi, M., Experimental investigation on the aerodynamic behavior of square cylinders with rounded corners. J. Fluids Struct. 44 (2014), 195–204.
Cimarelli, A., Leonforte, A., Angeli, D., Direct numerical simulation of the flow around a rectangular cylinder at a moderately high Reynolds number. J. Wind Eng. Ind. Aerod. 174 (2018), 39–49.
Guissart, A., Numerical and Experimental Study of Bluff Body Aerodynamics. Ph.D. thesis, 2017, Université de Liège.
Irwin, P.A., Bluff body aerodynamics in wind engineering. J. Wind Eng. Ind. Aerod. 96 (2008), 701–712.
Li, Y., Tang, H., Lin, Q., Chen, X., Vortex-induced vibration of suspenders in the wake of bridge tower by numerical simulation and wind tunnel test. J. Wind Eng. Ind. Aerod. 164 (2017), 164–173.
Mannini, C., Marra, A.M., Pigolotti, L., Bartoli, G., The effects of free-stream turbulence and angle of attack on the aerodynamics of a cylinder with rectangular 5:1 cross section. J. Wind Eng. Ind. Aerod. 161 (2017), 42–58.
Mannini, C., Šoda, A., Schewe, G., Unsteady RANS modelling of flow past a rectangular cylinder: investigation of Reynolds number effects. Comput. Fluid 39 (2010), 1609–1624.
Mannini, C., Šoda, A., Schewe, G., Numerical investigation on the three-dimensional unsteady flow past a 5:1 rectangular cylinder. J. Wind Eng. Ind. Aerod. 99 (2011), 469–482.
Mariotti, A., Salvetti, M.V., Shoeibi Omrani, P., Witteveen, J.A.S., Stochastic analysis of the impact of freestream conditions on the aerodynamics of a rectangular 5:1 cylinder. Comput. Fluid 136 (2016), 170–192.
Menter, F., Esch, T., Elements of industrial heat transfer predictions. 16th Brazilian Congress of Mechanical Engineering, 2001, COBEM), 26–30.
Menter, F.R., Kuntz, M., Langtry, R., Ten years of industrial experience with the SST turbulence model. Turbulence, heat and mass transfer 4 (2003), 625–632.
Mizota, T., Okajima, A., Experimental studies of unsteady flows around rectangular prisms. Proceedings of the Japan Society of Civil Engineers, 1981, 49–57.
Nakaguchi, H., Hashimoto, K., Muto, S., An experimental study on aerodynamic drag of rectangular cylinders. J. Japan Soc. Aeronautic. Eng. 16 (1968), 1–5.
Nakamura, Y., Mizota, T., Torsional flutter of rectangular prisms. J. Eng. Mech., 101, 1975.
Okajima, A., Flow around a rectangular cylinder with a section of various width/height ratios. Wind Engineers, 1983, 1–19 JAWE 1983.
Patruno, L., Ricci, M., de Miranda, S., Ubertini, F., Numerical simulation of a 5:1 rectangular cylinder at non-null angles of attack. J. Wind Eng. Ind. Aerod. 151 (2016), 146–157.
Ricci, M., Patruno, L., de Miranda, S., Ubertini, F., Flow field around a 5:1 rectangular cylinder using les: influence of inflow turbulence conditions, spanwise domain size and their interaction. Comput. Fluid 149 (2017), 181–193.
Rigo, F., Denoël, V., Andrianne, T., Vortex induced vibrations of rectangular cylinders arranged on a grid. J. Wind Eng. Ind. Aerod. 177 (2018), 327–339.
Robertson, J.M., Cermak, J.E., Nayak, S.K., A Reynolds-number effect in flow past prismatic bodies. Mech. Res. Commun. 2 (1975), 279–282.
Robertson, J.M., Wedding, J.B., Peterka, J.A., Cermak, J.E., Wall pressures of separation-reattachment flow on a square prism in uniform flow. J. Wind Eng. Ind. Aerod. 2 (1978), 345–359.
Schewe, G., Reynolds-number-effects in flow around a rectangular cylinder with aspect ratio 1:5. J. Fluids Struct. 39 (2013), 15–26.
Schmid, P.J., Dynamic mode decomposition of numerical and experimental data. J. Fluid Mech. 656 (2010), 5–28.
Shimada, K., Ishihara, T., Application of a modified k−εmodel to the prediction of aerodynamic characteristics of rectangular cross-section cylinders. J. Fluids Struct. 16 (2002), 465–485.
Shirato, H., Sato, Y., Sasaki, O., Van Bao, D., Coherent structure of surface pressures on 2-D rectangular cylinders. Proceedings of the Fifth International Symposium on Computational Wind Engineering, 2010, Chapel Hill, North Carolina, USA.
Shur, M., Spalart, P.R., Squires, K.D., Strelets, M., Travin, A., Three-dimensionality in Reynolds-averaged Navier-Stokes solutions around two-dimensional geometries. AIAA J. 43 (2005), 1230–1242.
Spalart, P.R., Jou, W.H., Strelets, M., Allmaras, S.R., others, Comments on the feasibility of LES for wings, and on a hybrid RANS/LES approach. Advances in DNS/LES 1 (1997), 4–8.
Spalart, P.R., Streett, C., Young-Person’ S Guide to Detached-Eddy Simulation Grids., 2001, National Aeronautics and Space Administration, Langley Research Center Technical Report.
Stokes, A.N., Welsh, M.C., Flow-resonant sound interaction in a duct containing a plate, II: square leading edge. J. Sound Vib. 104 (1986), 55–73.
Tamura, T., Itoh, Y., Kuwahara, K., Computational separated-reattaching flows around a rectangular cylinder. J. Wind Eng. Ind. Aerod. 50 (1993), 9–18.
Tamura, T., Miyagi, T., Kitagishi, T., Numerical prediction of unsteady pressures on a square cylinder with various corner shapes. J. Wind Eng. Ind. Aerod. 74–76 (1998), 531–542.
Wang, X., Gu, M., Experimental investigation of Reynolds number effects on 2d rectangular prisms with various side ratios and rounded corners. Wind Struct. Int. J. 21 (2015), 183–202.
Washizu, K., Ohya, A., Otsuki, Y., Fujii, K., Aeroelastic instability of rectangular cylinders in a heaving mode. J. Sound Vib. 59 (1978), 195–210.
Yu, D., Kareem, A., Parametric study of flow around rectangular prisms using LES. J. Wind Eng. Ind. Aerod. 77–78 (1998), 653–662.
