方形截面飞行器上仰机动对滚转特性影响的数值模拟

发布时间：2018-09-17 13:51

【摘要】：飞行器从中小迎角至大迎角范围内,由于背风区流动分离形态的演化,静态气动特性特别是横侧向气动特性也随迎角显著变化,可能诱发复杂的滚转运动。但飞行器一般是上仰机动时,才从平飞状态快速拉起至大迎角,此机动过程对横侧向气动特性和滚转运动可能产生较大影响。本文发展了刚体动力学方程和Navier-Stokes方程的松耦合求解技术,并通过数值模拟航天飞机脱落碎片的六自由度运动轨迹进行了验证。针对背风区涡流形态及横侧向气动特性复杂的方形截面飞行器,数值模拟研究了其不同迎角下的静态滚转气动特性、自由滚转运动特性,以及上仰机动时不同拉起速率对滚转运动特性的影响。结果表明,对于此飞行器,静态时存在临界迎角约为13°,当迎角小于临界迎角时,滚转方向是静不稳定的,诱发快速滚转运动;当迎角大于临界迎角时,滚转方向是静稳定的,其滚转运动是收敛的。但上仰机动时,滚转运动的形态还与拉起速率相关,即使拉起的终止迎角大于临界迎角,如果拉起速率较慢,也可能出现快速滚转运动。
[Abstract]:In the range from small and medium angle of attack to high angle of attack, the static aerodynamic characteristics, especially the lateral aerodynamic characteristics, vary significantly with the angle of attack due to the evolution of the flow separation form in the leeward region, which may induce complex rolling motion. However, it is only when the aircraft moves upward that it starts rapidly from flat to high angle of attack, which may have a great influence on the lateral aerodynamic characteristics and roll motion. In this paper, the loosely coupled solution technique of rigid body dynamics equation and Navier-Stokes equation is developed, and verified by numerical simulation of six degrees of freedom motion trajectory of space shuttle shedding debris. The static roll aerodynamic characteristics and free roll motion characteristics of square cross section aircraft with complex vortex and lateral aerodynamic characteristics in the leeward region are numerically simulated at different angles of attack. And the effects of different lifting rates on the rolling motion characteristics. The results show that the critical angle of attack is about 13 掳in static state. When the angle of attack is less than the critical angle of attack, the rolling direction is static and unstable, which induces the fast rolling motion, and when the angle of attack is greater than the critical angle of attack, the rolling direction is statically stable. Its rolling motion is convergent. However, the shape of roll motion is also related to the pulling rate, even if the angle of attack is larger than the critical angle of attack, if the lifting rate is slow, the rapid rolling motion may occur.
【作者单位】：中国空气动力研究与发展中心计算空气动力研究所;
【基金】：国家自然科学基金(11372341,11532016)~~
【分类号】：V211.3

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