运动物体穿过深海密度分界面的水动力特性研究

项目名称： 运动物体穿过深海密度分界面的水动力特性研究

项目编号： No.11202047

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 王文华

作者单位： 大连理工大学

项目金额： 25万元

中文摘要： 本项目旨在提出一种求解运动物体和密度分界面相互作用的流场计算新方法，并且将其应用于工程新课题(在深海分层流体中悬吊结构物入水、下放过程的水动力特性分析)的研究，用以解决运动物体穿过深海自由液面和分层流体界面这一复杂的瞬态物理问题。 针对问题的难点，采用界面捕捉法处理瞬时移动的密度分界面，并且利用直角切割网格技术来解决动边界问题。本项目主要分析了入水流场和分层流体内波流场之间的相互影响，重点探讨了各种界面波(表面波浪和内波)对运动物体的水动力作用，最后比较了模型实验和数值计算结果，用以验证本项目的研究方法、模型和结论。 本项目创新性地将自由液面和分层流体界面统一为流体密度分界面，采用相同的流场计算方法进行研究，能够更好地分析不同性质的密度分界面对运动物体所受水动力的影响，用以指导深海结构物的悬吊下水作业，并能为工程领域的相关问题提供理论模型和流场算法。

中文关键词： 运动物体；自由液面；分层流体内波；界面捕捉法；直角切割网格

英文摘要： For the new deepwater project(water-entry and lowering operation of subsea structure in deepwater stratified fluid), in order to solve difficult physical problem of moving structure through free surface and stratified fluid interface, the research presents a new method to calculate the interaction of moving body and density interface. In the new method, surface capturing method is applied to handle instantaneous shifting density interface, and Cartesian cut cell mesh is adopted to solve the difficulty of moving boudanry. By this method, the interaction of various fluid fields between water entry and internal wave is mainly studied, and then hydrodynamic effects of surface wave and internal wave on moving body are detailedly discussed. Furthermore, in order to verify the calculation model and conclusions, many model tests are designed and compared with numerical results. In summary, this research creatively unifies free surface and stratified fluid interface together as density interface, which can be handled and studied by the same calculation method. Thus, by combining water entry with internal wave problem, the influence of various density interfaces on moving body can be better analyzed. Finally, the calculation model and method can be provided for practical engineering to guide the lowering operation of subs

英文关键词： moving body；free surface；stratified internal wave；surface capturing method；Cartesian cut cell mesh