地面对双轨超声速火箭橇的气动特性影响研究

Effect of Ground on Aerodynamic Performance of a Double-track Supersonic Rocket-sled

地面对动态滑行状态下双轨火箭橇的气动特性有较大影响。本文采用尺度自适应(SAS)方法和动网格方法结合的策略对Ma 2的双轨火箭橇进行数值模拟,研究了地面导致的流场变化、气动力及其时域和频域特性。结果表明,激波和压缩波在地面设施的反射会导致双轨火箭橇下表面出现6处额外的高压区,其中4处的形状和强度会随反射位置发生变化;地面导致升力时均值提升了9.6倍;气动力呈现明显的同频周期性振荡,升力振荡幅值为时均值的28.6%,阻力振荡较小。为双轨火箭橇的减阻减振工作提供参考依据。

The aerodynamic characteristics of the rocket sled are significantly influenced by the ground as the rocket sled moves along the track.To analyze the flow field and force characteristics of the double-track rocket sled,changes in the flow field,time-averaged force and their characteristics in both time and frequency domain are investigated using scale adaptive simulation(SAS)and the dynamic mesh method at a Ma 2.The results show that the reflection of shock waves and compression waves on the ground facilities could lead to 6 extra high-pressure areas on the lower surface of the double-track rocket sled,and 4 of them could change with different reflection positions.The ground environment causes the time-average lift to increase by 9.6 times.The pressure signal and instantaneous aerodynamic force indicate strict periodic oscillation at the same frequency,the amplitude of the lift oscillation is 28.6%of the lift showing a lower drag oscillation.The present findings would contribute to the drag and vibration reduction of the double-track rocket sled.