Evolution of the vortex structures and turbulent spots at the late-stage of transitional boundary layers
Tóm tắt
The nonlinear evolution process of new vortex structures at the late-stage of the transition, including the 3-D spatial structure of barrel-shaped vortex and “dark spots”structure observed by experiment research, has been confirmed by our computational results. The formation mechanisms of these structures have been explored. It is revealed that the new vortex structures, the ring-like vortex chain and induced disturbance velocities play a dominant role in the generation of turbulent spots.
Tài liệu tham khảo
Kachanov Y S. On a universal nonlinear mechanism of turbulence production in wall shear flows. In: 10th Int. Conference on Methods of Aerophysical Research. Proceedings. Part 2. Novosibirsk: Inst. Theor. & Appl. Mech., 2000. 84–91
Blackwelder R F. Analogies between transitional and turbulent boundary layers. Phys Fluids, 1983, 26: 2807–2815
Borodulin V I, Gaponenko V R, Kachanov Y S, et al. Late-stage transitional boundary-layer structures. Direct numerical simulation and experiment. Theoret Comp Fluid Dyn, 2002, 15: 317–337
Chen L, Tang D B, Liu X B, et al. Evolution of the ring-like vortices and spike structure in transitional boundary layers. Sci China Phys Mech Astron, 2010, 53: 514–520
Wang J J, Pan C, Guo H, et al. Sweep and ejection events in transitional boundary layer. Synchronous visualization and spatial reconstruction. In: 13th Intl Conf. on Methods of Aerophysical Research. Proceedings. Part V. Novosibirsk: Publ. House “Parallel”, 2007. 192–197
Das A, Mathew J. Direct numerical simulation of turbulent spots. Computers & Fluids, 2001, 30: 532–541
Bake S, Meyer D G W, Rist U. Turbulence mechanism in Klebanoff transition: A quantitative comparison of experiment and direct numerical simulation. J Fluid Mech, 2002, 459: 217–243
Li X L, Fu D X, Ma Y W. Direct numerical simulation of transition to turbulence in a compressible blunt-wedge boundary layer. Sci China Ser G-Phys Mech Astron, 2004, 34: 466–480
Duan L, Wang X, Zhong X L. A high-order cut-cell method for numerical simulation of hypersonic-boundary transition with surface roughness. AIAA Paper, 2008, AIAA-2008-3732
Meyer D, Rist U, Kloker M. Investigation of the flow randomization process in a transitional boundary layer. In: E. Krause, W. Jäger and M. Resch, Eds. High Performance Computing in Science and Engineering’ 03. Berlin, Heidelberg: Springer, 2003. 239–254
Zhang L, Tang D B. Nonlinear evolution of turbulent spots in the near-wall shear flow. Sci China Ser G-Phys Mech Astron, 2006, 49: 128–138
Malik M R. Numerical methods for hypersonic boundary layer stability. J Comput Phys, 1990, 86: 376–413
Jiang L, Shan H, Liu C. Non-reflecting boundary conditions for DNS in curvilinear coordinates. In: Recent Advances in DNS and LES. Proceedings of the Second AFOSR International Conference on DNS/LES. Rutgers — The State University of New Jersey, New Brunswick, U.S.A., June 7–9, 1999
Chen L, Tang D B. Navier-Stokes characteristic boundary conditions for simulations of some typical flows. Appl Math Sci, 2010, 4: 879–893
Jeong J, Hussain F. On the identification of a vortex. J Fluid Mech, 1995, 285: 69–94
Borodulin V I, Kachanov Y S, Roschektayev A P. Experimental study of late stages of the laminar-turbulent transition in a boundary layer with an adverse pressure gradient. Thermophys Aeromech, 2003, 10: 1–26
Singer B A, Joslin R D. Metamorphosis of a hairpin vortex into a young turbulent spot. Phys Fluids, 1994, 6: 3724–3736