Affiliation:
1. State Key Laboratory of High Temperature Gas Dynamics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
2. School of Engineering Science, University of Chinese Academy of Sciences, Beijing 100049, China
Abstract
Suppressing shock-induced flow separation has been a long-standing problem in the design of supersonic vehicles. To reduce the structural and design complexity of control devices, a passive control technique based on micro-serrations is proposed and its controlling effects are preliminarily investigated under test conditions in which the Mach number is 2.5 and the ramp creating an incident shock is 15 deg. Meanwhile, a vorticity-based criterion for assessing separation scales is developed to resolve the inapplicability of the zero skin friction criterion caused by wall unevenness. The simulations demonstrate that the height of the first stair significantly influences the separation length. Generally, the separation length is shorter at higher stairs, but when the height is greater than half of the thickness of the incoming boundary layer, the corresponding separation point moves upstream. A stair with a height of only 0.4 times the thickness of the boundary layer reduces the separation length by 2.69%. Further parametric analysis reveals that while the remaining serrations have limited effects on the flow separation, an optimization of their shape (depth and width) can create more favorable spanwise vortices and offer a modest improvement of the overall controlling performance. Compared to the plate case, a 9.13% reduction in the separation length can be achieved using a slightly serrated design in which the leading stair is 0.1 high and the subsequent serrations are 0.2 deep and 0.05 wide (nondimensionalized, with the thickness of the incoming boundary layer). Meanwhile, the micro-serration structure even brings less drag. Considering the minor modification to the structure, the proposed method has the potential for use in conjunction with other techniques to exert enhanced control on separations.
Funder
National Natural Science Foundation of China
Reference45 articles.
1. Flame propagation and stabilization in dual-mode scramjet combustors: A survey;Huang;Prog. Aerosp. Sci.,2018
2. Large-eddy simulation of passive shock-wave/boundary-layer interaction control;Pasquariello;Int. J. Heat Fluid Flow,2014
3. Progress of shockwave/boundary layer interaction and its control in inlet;Zhang;J. Propuls. Technol.,2020
4. Shock wave boundary layer interaction;Hadjadj;Shock Waves,2009
5. Self-excited oscillations in internal transonic flows;Meier;Prog. Aerosp. Sci.,1990
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
1. Shock-Dominated Flow;Aerospace;2024-08-21