Numerical Simulation on the Stability of Hypersonic Base Flow over Blunt Body and Study of Instability Characteristics
The structural instabilities of base flow in hypersonic wake flow over sphere or blunt cone are investigated by numerical simulation in this paper. Numerical simulation method is second-order accuracy NND scheme in spatial direction and Second-order Runge-Kutta scheme in temporal direction. Wakes flow of sphere at M∞,=2, Re=1.71E+6(based on the sphere radius) and at M∞=6, Re=1.71E+6 are simulated and wakes flow of blunt cone at M∞=6, Re=1.71E+6(based on the nose radius) is done. Stable solutions are obtained and there are a primary separation and a secondary separation zone in flow over sphere at M∞=2 and M∞=6. Later, without any arbitrary disturbance imposed, the structural instability still occurs after a certain critical time. The evolving process of the structure of flow over sphere is a periodic behavior in the forepart, but it evolves into a nonperiodic behavior after a critical time at M∞=2. In the period time, the topological structures of the flow field over sphere and their evolving process at Ho=6 are similar to that of Mo=2, but there is nonperiodic behavior observed at M∞=6 in spite of long calculation time. For blunt cone, the simulation result is similar to that of a sphere under the condition of M∞=6, Re=1.71E+6. This study result indicates that the present numerical simulation method can be used for the study of the stability of base flow and confirms that hypersonic flow at the base is also instability.
Dehua Zhu Qing Shen Qiang Wang Xiangjiang Yuan
China Academy of Aerospace Aerodynamics, Beijing, P .R. China, 100074
国际会议
The 8th Sino-Russia High-speed Flow Conference(第八届中俄高超声速流体力学研讨会)
上海
英文
330-340
2011-11-21（万方平台首次上网日期，不代表论文的发表时间）