In engineering applications (Like an ocean riser), fluid flow around bluff bodies generates substantial resistance, which can jeopardize structural integrity, lifespan, and escalate resource consumption. Therefore, employing drag reduction measures becomes particularly crucial. This paper employs the immersed boundary method to investigate the impact of transversely oriented appendage plate flexibility on the drag of cylinders under different Reynolds numbers and distances. The results indicate that flexible appendage plate exerts drag reduction effects on the downstream cylinder, with this effect gradually diminishing as Reynolds numbers increase. At identical Reynolds numbers, the drag reduction effect initially increases and then decreases with distance, with the optimal drag reduction distance observed at D = 2.5. Compared to cylinders without appendage plate, the maximum drag reduction achieved is 30.551%. Addressing the drag reduction issue in cylinders holds significant importance for ensuring engineering structural integrity, enhancing engineering efficiency, and developing novel underwater towing systems.
References
[1]
Ji, W.Y. (2008) Three-Dimensional Numerical Simulation Study on the Drag Reduction Characteristics of Cylinder Flow around Appendages. Harbin Institute of Technology, Harbin. (In Chinese)
[2]
Su, L.G., Gu, J.J., Duan, M.L., et al. (2015) Analysis of Flow Field Characteristics around Cylinder Based on CFD. Oil Field Equipment, 44, No. 4. (In Chinese)
[3]
Song, Z.H. and Duan, M.L. (2016) Study on the Suppression Effect of Three Appendages on Vortex Shedding of Marine Risers. Petroleum Machinery, 44, No. 6. (In Chinese)
[4]
Liu, F.X. (2019) Numerical Simulation Study on the Influence of Appendages on Cylinder Vibration and Wind Energy Harvesting Characteristics. Harbin Institute of Technology, Harbin. (In Chinese)
[5]
Achenbach, E. (1968) Distribution of Local Pressure and Skin Friction around a Circular Cylinder in Cross-Flow up to Re = 5 × 106. Journal of Fluid Mechanics, 34, 625-639. https://doi.org/10.1017/S0022112068002120
[6]
Izutsu, N. (1993) Fluid Force Measurements for a Circular Cylinder with a Slit. Nagare, 12, 293-301.
[7]
Yajima, Y. and Sano, O. (1996) A Note on the Drag Reduction of a Circular Cylinder due to Double Rows of Hole. Fluid Dynamics Research, 18, 237-243. https://doi.org/10.1016/0169-5983(96)00015-9
[8]
Lesage, F. and Gartshore, I.S. (1987) A method of Reducing Drag and Fluctuating Side Force on Bluff Bodied. Journal of Wind Engineering and Industry Aerodynamics, 25, 229-245. https://doi.org/10.1016/0167-6105(87)90019-5
[9]
Alonzo-García, A., et al. (2021) The Control of Unsteady Forces and Wake Generated in Circular and Square Cylinder at Laminar Periodic Regime by Using Different Rod Geometries. Ocean Engineering, 233, Article ID: 109121. https://doi.org/10.1016/j.oceaneng.2021.109121
[10]
Prasad, A. and Williamson, C.H.K. (1997) A Method for the Reduction of Bluff Body Drag. Journal of Wind Engineering and Industrial Aerodynamics, 69-71, 155-167. https://doi.org/10.1016/S0167-6105(97)00151-7
[11]
Jiang, X.L., Ouyang, L.H. and Li, C. (2022) Research on Drag Reduction Performance of Cylinder Based on Surface V-Shaped Grooves. Digital Ocean and Underwater Defense, 5, No. 2. (In Chinese)
[12]
Lin, X., He, G., He, X., Wang, Q. and Chen, L. (2017) Numerical Study of the Hydrodynamic Performance of Two Wiggling Hydrofoils in Diagonal Arrangement. Journal of Applied Mathematics and Physics, 3, 31-38. https://doi.org/10.4236/jamp.2017.51005
