Transient Response of Enstrophy Transport to Opposition Control in Turbulent Channel Flow
-
摘要: 利用直接数值模拟研究了槽道湍流中脉动拟涡能输运对反向控制的瞬时响应. 发现流向和展向拟涡能的衰减首先由拉伸产生项的抑制引起,而法向拟涡能的减小是因为控制阻碍了平均剪切的倾斜.在控制的初始阶段,流向拟涡能的演化远远落后于其它两个分量的变化.法向涡量快速单调减小,并对其它两个分量的减弱起到了重要作用.Abstract: The transient response of turbulent enstrophy transport to opposition control in turbulent channel flow was studied with the aid of direct numerical simulation. It is found that the streamwise and spanwise enstrophy are suppressed by the attenuation of the stretching terms at first, while the vertical enstrophy is reduced by inhibiting the tilting of mean shear. During the initial period of the control, the streamwise enstrophy evolves much slower than the other two components. The vertical vorticity component exhibits a rapid monotonic decrease and also plays an important role in the attenuation of the other two components.
-
[1] Kravchenko A G, Choi H, Moin P.On the relation of nearwall streamwise vortices to wall skin friction in turbulent boundary layers[J]. Phys Fluids A,1993, 5(12): 3307-3310. [2] Orlandi P, Jimenez J.On the generation of turbulent wall friction[J]. Phys Fluids,1994, 6(2): 634-641. [3] Fukagata K, Iwamoto K, Kasagi N.Contribution of Reynolds stress distribution to the skin friction in wall-bounded flows[J]. Phys Fluids,2002, 14(11): L73-L76. Choi H, Moin P, Kim J.Active turbulence control for drag reduction in wall-bounded flows[J]. J Fluid Mech,1994, 262: 75-110. [4] Lee C, Kim J, Choi H.Suboptimal control of turbulent channel flow for drag reduction[J]. J Fluid Mech,1998, 358: 245-258. [5] Endo T, Kasagi N, Suzuki Y.Feedback control of wall turbulence with wall deformation[J]. International Journal of Heat and Fluid Flow,2000, 21(5): 568-575. [6] Kim J.Physics and control of wall turbulence for drag reduction[J]. Phil Trans R Soc A,2011, 369(1940): 1396-1411. [7] Quadrio M, Ricco P.Initial response of a turbulent channel flow to spanwise oscillation of the walls[J]. J Turb,2003, 4: 1-23. [8] Xu C X, Huang W X.Transient response of Reynolds stress transport to spanwise wall oscillation in a turbulent channel flow[J]. Phys Fluids,2005, 17(1): 1-4. [9] Ge M W, Xu C X, Cui G X.Transient response of Reynolds stress transport to opposition control in turbulent channel flow[J]. Sci China,2011, 54(2): 320-328. [10] Xu C, Zhang Z, Nieuwstadt F T M, Toonder den J M J.Origin of high kurtosis levels in the viscous sublayer: direct numerical simulation and experiment[J]. Phys Fluids,1996, 8(7): 1938-1944. [11] Hammond E P, Bewley T R, Moin P.Observed mechanisms for turbulence attenuation and enhancement in oppositioncontrolled wallbounded flows[J]. Phys Fluids,1998, 10(9): 2421-2423. [12] Johanson A V, Alfredsson P H, Kim J.Evolution and dynamics of shearlayer structures in nearwall turbulence[J]. J Fluid Mech,1991, 224: 459-599. [13] Hamilton J M, Kim J, Waleffe F.Regeneration mechanism of near wall turbulence structures[J]. J Fluid Mech,1995, 287: 317-348.
点击查看大图
计量
- 文章访问数: 1420
- HTML全文浏览量: 87
- PDF下载量: 1041
- 被引次数: 0