激波两次冲击下重气柱Richtmyer-Meshkov不稳定性的粒子图像测速研究

发布时间：2018-07-03 11:44

本文选题：Richtmyer-Meshkov不稳定性 + 二次冲击　；参考：《高压物理学报》2016年06期

【摘要】：采用粒子图像测速(PIV)技术,实验研究了激波两次冲击空气环境中重气体SF6气柱的Richtmyer-Meshkov(RM)不稳定性,定量表征了流场的速度、涡量和环量。结果表明,激波首次冲击气柱后,界面演化成初始涡对,且在较长时间内涡强度的变化很小。激波二次冲击气柱后:当反射距离较小时,界面衍生出二次涡对,其旋转方向与初始涡对的旋转方向相反,强度显著小于初始涡对的强度;当反射距离较大时,则不衍生大尺度涡结构。初始涡对的环量在激波二次冲击气柱后随时间逐渐减小,说明能量逐渐由流场中的大尺度结构转移至小尺度结构。利用PIV技术得到的初始涡对和二次涡对的环量与理论模型的预测结果吻合较好。
[Abstract]:The Richtmyer-Meshkov (RM) instability of a heavy gas SF _ 6 gas column in a two-shock impact air environment was experimentally studied by particle image velocimetry (PIV) technique. The velocity, vorticity and annulus of the flow field were quantitatively characterized. The results show that the interface evolves into an initial vortex pair after the shock wave hits the gas column for the first time, and the variation of the vorticity intensity is very small in a long period of time. When the reflection distance is small, the secondary vortex pair is derived from the interface. The rotation direction of the secondary vortex pair is opposite to that of the initial vortex pair, and the intensity of the initial vortex pair is significantly lower than that of the initial vortex pair, and when the reflection distance is large, The large scale vortex structure is not derived. The annulus of the initial vortex pair decreases with time after the shock wave impinges on the gas column, indicating that the energy is gradually transferred from the large scale structure in the flow field to the small scale structure. The initial vortex pair and the secondary vortex pair obtained by the PIV technique are in good agreement with the predicted results of the theoretical model.
【作者单位】：中国工程物理研究院流体物理研究所冲击波物理与爆轰物理实验室;
【基金】：国家自然科学基金(11172278,11472253,11302201) 中国工程物理研究院科学技术发展基金(2014B0201017)
【分类号】：O354.5

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