冲击波与气泡帷幕相互作用机理研究

Bubble curtain technology could effectively reduce shock load and bubble load in underwater explosion，resulting in its important military and civil applications. The two core problems in this field are: the interaction of a shock wave with a bubble curtain, and the interaction of a large-scale bubble with a bubble curtain. We will develop the theoretical and numerical models for the interaction between a shockwave and a bubble curtain, verify the validity of the models by experiments and conclude the application range of different theoretical and numerical model by comparing the different theoretical and numerical models. We will develop the theory and method and numerical model for the interaction of a large-scale bubble with a bubble curtain. Through theoretical derivation, we obtain analytic solutions to the interaction of large bubble and small scale bubbles, then establish a numerical model of large bubble and small scale bubbles in weak compressible and strong compressible flow field, and considering the influence of complex boundary, explore large bubbles and small bubbles coupling characteristics. We will develop the experimental facilities for the interaction of a shockwave and a bubble curtain as well as the interaction of a large bubble and a bubble curtain, using spark generated bubbles. The experimental data will be used to validate the models developed in the project. With computational and experimental capabilities developed, we will study the mechanisms of shockwave attenuation due to a bubbly curtain and its effects to large scale bubble dynamics. We will perform the parametric study to optimize protective effects of a bubble curtain. This study aims to providing the reference for underwater explosion anti-shock.

气泡帷幕可以有效的降低水下爆炸载荷，广泛应用于军事和工程。气泡帷幕抗冲击中的两个核心问题是：冲击波与气泡群的相互作用和大尺度气泡与气泡群的耦合作用。依据具体问题中流场中流场可压缩性的强弱，分别建立冲击波和气泡帷幕相互作用的不同的理论模型和数值模型，通过实验验证所建立模型的有效性，并通过不同数值模型相互验证和比较，得到不同理论和数值模型的适用范围。还将发展大尺度气泡与气泡帷幕相互作用的理论方法和数值模型，首先通过理论推导，得到大尺度气泡和小尺度气泡相互作用的解析解，然后建立弱可压缩和强可压缩流场中大尺度和小尺度气泡的数值模型。考虑复杂边界的影响，探究在复杂边界条件下大气泡和小气泡耦合特性。同时，发展减压电火花气泡与常压上浮气泡群相互作用的实验装置，研究气泡帷幕对冲击波的衰减机理和对大尺度气泡运动的影响。优化气泡帷幕形态，以取得最佳抗冲击防护效果。旨在为水下爆炸抗冲击提供参考。

水下爆炸过程中产生的高频冲击波载荷通常对船体结构造成局部毁伤，而低频多周期的气泡载荷往往引起舰船的鞭状运动，进而威胁舰船的总纵强度。气泡帷幕可以有效降低水下爆炸载荷，因此研究冲击波与气泡帷幕相互作用机理在重要的科学意义和工程应用价值。气泡帷幕抗水下爆炸冲击的核心科学问题为冲击波与多气泡的相互耦合作用及大尺度气泡与小尺度气泡的相互耦合作用问题，目前为止，国内外研究人员采用理论分析和实验方法初步探索了气泡帷幕对冲击波的衰减过程，但对于冲击波与气泡帷幕（多气泡）的相互作用机理仍有待进一步揭示。鉴于此，本项目建立冲击波与多气泡的相互作用模型和计算方法，以及大尺度气泡与小尺度气泡的耦合模型和计算方法。在此基础上，引入复杂边界的大气泡和小气泡的非线性耦合效应，同时对不同尺度气泡间的相互作用进行实验研究，进而揭示水下爆炸气泡构成的“气泡帷幕”的抗冲击机理。通过以上研究，为气泡帷幕抗冲击的相关研究工作提供基础理论和可行性技术支撑，为气泡帷幕在船舶与海洋工程领域应用过程（资源开发、舰艇防护等）中的实际动力学特性研究提供有力的参考依据。