An experimental study on chaotic oscillation of a chined forebody configuration in roll

作者：Shi Wei^*; Deng Xueying; Wang Yankui; Li Qian; Tian Wei

来源：Experiments in Fluids, 2015, 56(9): 175.

DOI：10.1007/s00348-015-2048-x

The chaotic oscillation is an aperiodic oscillation rolling between a positive and a negative equilibrium positions with a chaotic behavior. This oscillation pattern was investigated over a chined forebody configuration through a series of wind tunnel tests at an angle of attack of 40 degrees with a Reynolds number of 1.87 x 10(5). The wing vortex flow around zero roll angle induced by the forebody asymmetric vortices flow is crucial to the motion. Under static conditions, the strong leeward wing vortex causes the unstable lateral stability around zero roll angle and leads to the formation of a positive and a negative stable equilibrium position of the rolling moment, which is considered as the premise of forming the motion. The strong leeward wing vortex at a low angular velocity can stop the model from crossing zero roll angle and drive the model to increase amplitude, which is the key to explain the flow mechanism. Weakening of the leeward wing vortex due to a prominent hysteresis at a high angular velocity make the model cross zero roll angle, but the appearance of the strong windward vortex after crossing zero roll angle decelerates the rolling motion and makes the amplitude decrease.

• 出版日期2015-9
• 单位北京航空航天大学