Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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Numerical Simulation of Flow around Variable Pitch Helically Elliptic Twisted Cylinder based on the Biomimetic Flow Control

생체모방 유동제어 기반 가변 피치 나선형 실린더 주위 유동 해석

  • Moon, Jahoon (Department of Naval Architecture and Ocean Engineering, Pusan National University) ;
  • Yoon, Hyun Sik (Department of Naval Architecture and Ocean Engineering, Pusan National University)
  • 문자훈 (부산대학교 조선해양공학과) ;
  • 윤현식 (부산대학교 조선해양공학과)
  • Received : 2019.12.31
  • Accepted : 2020.02.21
  • Published : 2020.04.20
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Abstract

The new geometric disturbance is proposed to control the flow around the bluff body. The new geometry is characterized by the variable pitch which is applied on the Helically Elliptic Twisted (HET) cylinder. The performance of the HTE geometry as a biomimetic passive flow control was confirmed by Jung and Yoon (2014). The Large Eddy Simulation (LES) is used for the evaluation of the flow control performance of the Variable Pitch HTE (VPHTE) cylinder at Reynolds number (Re) of 3000 corresponding to the subcritical regime. The circular and HTE cylinders are also considered to compare the performance of the VPHTE cylinder at the same Re. The VPHTE cylinder gives the smallest values of the force coefficients than the circular and HTE cylinders. The drag and lift coefficients of the VPHTE cylinder are about 15.2% and 94.0% lower than those of the circular cylinder, respectively. Especially, the VPHTE cylinder achieves about 2.3% and 30.0% reduction of the drag coefficient and the root mean square of the lift coefficient than the HTE cylinder, respectively. Furthermore, The VPHTE cylinder forms more elongated and stabilized separated shear layer than the circular cylinder, which supports the reduction of the force coefficients.

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References

  1. Ahmed, A. & Bays-Muchmore, B., 1992. Transverse flow over a wavy cylinder. Physics of Fluids A, 4(9), pp.1959-1967. https://doi.org/10.1063/1.858365
  2. Bearman, P.W., 1965. Investigation of the flow behind a two-dimensional model with a blunt trailing edge and fitted with splitter plates. Journal of Fluid Mechanics, 21(2), pp.241-255. https://doi.org/10.1017/S0022112065000162
  3. Chen, Z.S. & Kim, W.J., 2010. Numerical investigation of vortex shedding and vortex-induced vibration for flexible riser models. International Journal of Naval Architecture and Ocean Engineering, 2(2), pp.112-118. https://doi.org/10.2478/IJNAOE-2013-0026
  4. Choi, H., Jeon, W. & Kim, J., 2008. Control of flow over a bluff body. Annual Review of Fluid Mechanics, 40(1), pp.113-139. https://doi.org/10.1146/annurev.fluid.39.050905.110149
  5. Chyu, C.K. & Rockwell, D., 2002. Near-wake flow structure of a cylinder with a helical surface perturbation. Journal of Fluids and Structures, 16(2), pp.263-269. https://doi.org/10.1006/jfls.2001.0419
  6. Germano, H., Piomelli, U., Moin, P. & Cabot, W.H., 1991. A dynamic subgrid-scale eddy viscosity model. Physics of Fluids A, 3(7), pp.1760-1765. https://doi.org/10.1063/1.857955
  7. Holmes, S. & Owen, H., 2006. Simulation of Riser VIV Using Fully Three Dimensional CFD Simulations. 25th International Conference on Offshore Mechanics and Arctic Engineering, Hamburg, Germany, 4-9 June 2006.
  8. Jeong, J. & Hussain, F., 1999. On the identification of a vortex. Journal of Fluid Mechanics, 285, pp.69-94. https://doi.org/10.1017/S0022112095000462
  9. Jung, J.H. & Yoon, H.S. 2014. Large eddy simulation of flow over a twisted cylinder at a subcritical Reynolds number. Journal of Fluid Mechanics, 759, pp.579-611. https://doi.org/10.1017/jfm.2014.581
  10. Kim, M.I. & Yoon, H.S. 2018. Large eddy simulation of forced convection heat transfer from wavy cylinders with different wavelength. International Journal of Heat and Mass Transfer, 127, pp.683-700. https://doi.org/10.1016/j.ijheatmasstransfer.2018.08.092
  11. Kim, W., Lee, J. & Choi, H., 2016. Flow around a helically twisted elliptic cylinder. Physics of Fluids, 28(5), 053602.
  12. Lam, K. & Lin, Y.F., 2008. Large eddy simulation of flow around wavy cylinders at a subcritical Reynolds number. Journal of Heat and Fluid Flow, 29(4), pp.1071-1088. https://doi.org/10.1016/j.ijheatfluidflow.2008.01.006
  13. Lam, K. Wang, F.H. Li, J.Y. & So, R.M.C., 2004a. Experimental investigation of the mean and fluctuating forces of wavy (varicose) cylinders in a cross-flow. Journal of Fluids and Structures, 19(3), pp.321-334. https://doi.org/10.1016/j.jfluidstructs.2003.12.010
  14. Lam, K. Wang, F.H. & So. R.M.C., 2004b. Three dimensional nature of vortices in the near wake of a wavy cylinder. Journal of Fluid and Structures, 19(6), pp.815-833. https://doi.org/10.1016/j.jfluidstructs.2004.04.004
  15. Lee, C.Y. et al., 2009. Characteristics of the Flow and Heat Transfer around a Wavy Cylinder. Journal of the Society of Naval Architects of Korea, 46(1), pp.1-9. https://doi.org/10.3744/SNAK.2009.46.1.001
  16. Lu, X., Dalton, C. & Zhang, J., 1997. Application of large eddy simulation to flow past a circular cylinder. ASME Journal of Offshore Mechanics and Arctic Engineering, 119, pp.219-225. https://doi.org/10.1115/1.2829099
  17. Noberg, C., 1987. Effects of Reynolds number and a low-intensity freestream turbulence on the flow around a circular cylinder. Publication 87/2, Department of Applied Thermodynamics and Fluid Mechanics, Chalmers University of Technology.
  18. Owen, J.C., Bearman, P.W. & Szewczyk, A.A., 2001. Passive control of VIV with drag reduction. Journal of Fluids and Structures, 15(3-4), pp.597-605. https://doi.org/10.1006/jfls.2000.0358
  19. Wei, D.J., Yoon, H.S. & Jung, J.H., 2016. Characteristics of aerodynamic forces exerted on a twisted cylinder at a low Reynolds number of 100. Computers and Fluids, 136, pp.456-466. https://doi.org/10.1016/j.compfluid.2016.07.002
  20. Yoon, H.S., Chun, H.H. & Lee, D.H., 2006. Numerical study on the fluid flow and heat transfer past a cylinder with a periodic array of circular fins. Journal of the Society of Naval Architects of Korea, 43(6), pp.285-293. https://doi.org/10.3744/SNAK.2006.43.3.285
  21. Yoon, H.S., Shin, H. & Kim, H., 2017. Asymmetric disturbance effect on the flow over a wavy cylinder at a subcritical Reynolds number. Physics of Fluids, 29(9), 095102.
  22. Zdravkovich, M.M., 1981. Review and classification of various aerodynamic and hydrodynamic means for suppressing vortex shedding. Journal of Wind Engineering and Industrial Aerodynamics, 7(2), pp.145-189. https://doi.org/10.1016/0167-6105(81)90036-2