基于相变松弛法则的水下爆炸空化模型研究  

Research on cavitation model of underwater explosion based on phase transition relaxation algorithm

作　　者：余俊[1] 王海坤[1] 刘建湖[1] 汪俊[1] 毛海斌[1] 周章涛[1] YU Jun;WANG Hai-kun;LIU Jian-hu;WANG Jun;MAO Hai-bin;ZHOU Zhang-tao(China Ship Scientific Research Center,Wuxi 214082,China)

机构地区：[1]中国船舶科学研究中心,无锡214082

出　　处：《计算力学学报》2022年第5期684-690,共7页Chinese Journal of Computational Mechanics

摘　　要：水下爆炸过程中存在着大量的空化现象,空化的产生、演化及其溃灭过程对于水下冲击波传播、爆炸气泡运动以及水下结构物冲击损伤都会产生重要影响。本文基于多相可压缩流体理论模型,考虑空化发生过程中汽-液两相流体亚平衡状态下两相之间发生的热力学-化学平衡机制,分析汽-液两相介质之间的质量和热量交换,从而实现对相变过程的自动捕捉。该系统的控制方程采用分步法处理,首先利用二阶MUSCL-Hancock格式和HLLC黎曼求解器来求解齐次双曲型方程,再采用牛顿迭代法求解相变方程。数值测试结果表明,本文的计算模型对于空化相变过程具有较好的捕捉能力。最后将该模型应用到水下近水面爆炸空化的数值模拟当中,研究发现空泡的溃灭压力峰值约为冲击波压力峰值的15%,有效作用时间是冲击波载荷有效作用时间的2倍以上。本文的空化相变模型能够为水下爆炸空化现象的机理研究提供重要支撑。There are a large number of cavitation phenomena in underwater explosion.The generation,evolution and collapse of cavitation play an important influence on the shock wave propagation,explosive bubble movement and structural impact damage.Based on multicomponent compressible flow theory,the thermodynamic-chemical equilibrium mechanism between liquid and vapor phases in metastable state is captured,which considering mass and heat exchange between the two phases.The control equations of the system are solved using a fractional step treatment.The homogenous hyperbolic system is solved by a second order MUSCL-Hancock and HLLC approximate Riemann solver firstly,and then Newton iterative method is used to deal with the phase transition relaxation model.The numerical test results show that this model provides a good ability to capture the phase transition in cavitation.Finally,the model is applied to simulate cavitation near water surface in underwater explosion.It is found that the collapsed pressure peak value of cavitation is about 15%of the shock wave pressure peak value,and the effective action time is more than 2 times of the effective action time of the shock wave.The cavitation phase transition model in this paper can provide an important support for the research of mechanism of underwater explosion cavitation.

关 键 词：多相可压缩流体 空化相变模型 水下爆炸 黎曼求解器 MUSCL-Hancock格式 

分 类 号：O354.5[理学—流体力学] O389[理学—力学]