大口径爆炸激波管出口冲击波流场图像测量

Image measurement of shock wave flow field at outlet of large diameter explosion shock tube

为了获取大视场下爆炸冲击波的纹影图像以及冲击波与被测模型相互作用后的流场演化特征,开展了基于聚焦纹影的反射式高速纹影测试。利用激光光源和高反射膜建立了系统所需的光源输入,并通过简化刀口栅设计,实现了远距离大口径爆炸激波管出口冲击波流场图像演化特征以及与固体模型相互作用的高时空分辨特征。研究结果表明,设计的聚焦式反射纹影系统在80 m以上距离处获取了大口径大当量爆炸激波管出口处6 m×3 m视场的冲击波特征,以及与固体相互作用的高时空分辨图像和状态数据;相比传统聚焦纹影系统,该系统具有结构简单、可实现性强、测试距离远,覆盖视场大等特点;通过设计不同光源输入,探讨了激光光源在远距离拍摄中的优势;通过冲击波阵面与固体模型的相互作用特征,揭示了冲击波作用于被测固体模型后的形成、演化和绕流状态。该测量结果能够为武器装备在受到冲击波作用后的状态评估和响应特性分析提供直观的图像数据支撑。

To capture schlieren images of explosion shock waves over a large field of view and analyze the flow field evolution after shock wave interaction with a model,a reflective high-speed schlieren measurement technique based on focused schlieren was developed.The system uses a laser source and high reflective film for input.By simplifying the knife-edge grid design,the shock wave flow field evolution at the outlet of a long-distance,large-aperture explosion shock tube and its high-resolution interaction with a solid model are achieved.At a distance of over 80 m,shock wave characteristics were obtained from a large-caliber,high-yield explosion shock tube with a 6 m×3 m field of view,along with high temporal and spatial resolution images and state data regarding interactions with solids.The study shows that the designed focused schlieren system is simpler,more feasible,and offers a longer test distance and wider field of view than traditional systems.By altering the light source input,the benefits of a laser source for long-distance imaging are explored.The interaction between the shock wave front and the solid model reveals the formation,evolution,and flow state of the shock wave on the model.These measurements provide visual data to support the evaluation and response analysis of weapons and equipment subjected to shock waves.