생체모방 유동제어 기반 가변 피치 나선형 실린더 주위 유동 해석
Numerical Simulation of Flow around Variable Pitch Helically Elliptic Twisted Cylinder based on the Biomimetic Flow Control
1
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
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 () 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 . 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.
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 () 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 . 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.
참고문헌 (22)
- Ahmed, A., "Transverse flow over a wavy cylinder", Physics of Fluids A, 4(9), pp.1959~1967 (1992)
- Bearman, P. W., "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 (1965)
- 전정수, "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 (2010), 대한조선학회
- Choi, H., "Control of flow over a bluff body", Annual Review of Fluid Mechanics, 40(1), pp.113~139 (2008)
- Chyu, C. K., "Near-wake flow structure of a cylinder with a helical surface perturbation", Journal of Fluids and Structures, 16(2), pp.263~269 (2002)
- Germano, H., "A dynamic subgrid-scale eddy viscosity model", Physics of Fluids A, 3(7), pp.1760~1765 (1991)
- Holmes, S., "Simulation of Riser VIV Using Fully Three Dimensional CFD Simulations", 25th International Conference on Offshore Mechanics and Arctic Engineering (2006)
- Jeong, J., "On the identification of a vortex", Journal of Fluid Mechanics, 285, pp.69~94 (1999)
- Jung, J. H., "Large eddy simulation of flow over a twisted cylinder at a subcritical Reynolds number", Journal of Fluid Mechanics, 759, pp.579~611 (2014)
- Kim, M. I., "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 (2018)
- Kim, W., "Flow around a helically twisted elliptic cylinder", Physics of Fluids, 28(5), pp.053602~ (2016)
- Lam, K., "Large eddy simulation of flow around wavy cylinders at a subcritical Reynolds number", Journal of Heat and Fluid Flow, 29(4), pp.1071~1088 (2008)
- Lam, K., "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 (2004)
- Lam, K., "Three dimensional nature of vortices in the near wake of a wavy cylinder", Journal of Fluid and Structures, 19(6), pp.815~833 (2004)
- 이창열, "파형 실린더 주위의 유동 및 열 전달 특성", 대한조선학회 논문집, 46(1), pp.1~9 (2009), 대한조선학회
- Lu, X., "Application of large eddy simulation to flow past a circular cylinder", ASME Journal of Offshore Mechanics and Arctic Engineering, 119, pp.219~225 (1997)
- Effects of Reynolds number and a low-intensity freestream turbulence on the flow around a circular cylinder, "Noberg, C.", Department of Applied Thermodynamics and Fluid Mechanics, Chalmers University of Technology, ~, pp.Publication 87 (1987), 2
- Owen, J. C., "Passive control of VIV with drag reduction", Journal of Fluids and Structures, 15(3-4), pp.597~605 (2001)
- Wei, D. J., "Characteristics of aerodynamic forces exerted on a twisted cylinder at a low Reynolds number of 100", Computers and Fluids, 136, pp.456~466 (2016)
- 윤현식, "원형 핀이 부착된 실린더 주위의 유동 및 열전달에 관한 수치적 연구", 대한조선학회 논문집, 43(3), pp.285~293 (2006), 대한조선학회
- Yoon, H. S., "Asymmetric disturbance effect on the flow over a wavy cylinder at a subcritical Reynolds number", Physics of Fluids, 29(9), pp.095102~ (2017)
- Zdravkovich, M. M., "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 (1981)