界面曲率对空化的演变及结构载荷的影响

详细信息

Effects of surface curvature on cavitation evolution and reloading

1.
School of Mathematics and System Sciences, Beihang University, Beijing 100191, China
2.
School of Civil and Environmental Engineering, Princeton University, NJ 08544, USA
3.
State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China

摘要: 研究了近体水下爆炸中结构表面外形的变化对空化的形成、演变及结构载荷的影响.为了真实地考虑流体与固体的非线性相互作用,近期发展的流--固耦合多介质Riemann问题技术和修正的虚拟介质方法被推广应用于处理流体与固体的相互作用中.研究发现, 凹的表面设计不但可以导致爆炸冲击波局部汇聚和强化,而且随后可以强化空化破裂所造成的冲击, 研究进一步发现,这种强化作用还是非线性的, 随曲率的增加而非线性增强; 相反地,凸的表面设计可以减低爆炸冲击波冲击,而且可以弱化空化的产生,但其影响是非常有限的.
- 空化再加载
Abstract: In this work,effects of surface curvature on cavitation evolution and structureloadings are investigated. We extended the latest techniques offluid-structure Riemann problem and the modified ghost fluidmethod to treat the flow-structure nonlinear interaction. Resultsdisclosed that a concave shape can strongly lead to not only shockfocus but also rarefaction wave intensification; suchintensification subsequently enhances local cavitation collapseand thus cavitation reloading. The magnitude of such enhancementincreases nonlinearly with the increase of surface curvature. Aconvex shape can weaken the shock impact and subsequent cavitationcollapse. However, such effect is well limited.
- cavitation reloading