Study on Numerical Methods for Flows with Moving Boundaries

动边界流数值方法研究

基本信息

批准号：
12650894
负责人：
TAKAKURA Yoko
金额：
$ 2.37万
依托单位：
Tokyo University of Agriculture and Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

As governing equations for numerical methods of flows with moving boundaries, usually used are the conservative form in general coordinate system in the case of compressible fluid, and the ALE (Arbitrary Lagrangian-Eulerian) form in the case of incompressible fluid, but these methods have the difficulty to re-generate grids at each time step when the boundaries are moving. On the other hand, the moving-coordinate method that the head investigator proposed is to resolve the difficulty. The purposes of this research project covers two intent : one is to give the unified derivation to the governing equations for numerical methods of flows with moving boundaries, which have existed individually, and give the scientific prospect to the field ; the other is to extend the ALE method and the moving-coordinate method for general use, apply them to physical and engineering problems, and enable to solve problems which cannot be solved because of the difficulty above statedIn the fiscal year of 20 … More 00, it was shown that the governing equations for numerical methods including moving boundaries, i.e., the conservative form in general coordinate system, the ALE (Arbitrary Lagrangian-Eulerian) form, and the moving-coordinate form, are derived unifiedly in this order, and simultaneously the meaning of the geometric conservation laws which metrics should satisfy was analytically 〓〓rified. Furthermore the moving-coordinate method was extended for general use, and applied to two cases with each way and flows : a 〓〓lti-domain problem for unsteady flows about a flying projectile launched in a ballistic range and a single-domain problem with cut-cell method for branch flows in opening process of a high-voltage gas circuit breaker. As results, it has been confirmed that the moving-coordinate method works effectively.In the fiscal year of 2001, the ALE form was extended to the general coordinate system, and applied to gun-tunnel flows. In the numerical computation there are two courses : to simulate complicated flows closer to real phenomena and obtain detail, and to model (simplify) and obtain practical information with less computing time. As an example of the latter course, the quasi-one-dimensional Euler equations including the change of cross area with not only space but also time were derived, the ALE method was correctly applied with modelling of the piston motion and the pressure loss. Through comparison with experiments, it has been confirmed that the extended ALE method works well.In the fiscal year 2002, the results obtained till then were published in international Journals with evaluation and consideration added. As preparatory stage to future developments, unstructured-grid solvers for arbitrary configuration and high-accurate schemes including source terms have been developed Less

作为管理界限的数值流量方法，通常使用的是一般坐标系统中的保守形式，在可压缩流体的情况下，在不可压缩的流体的情况下，ALE（任意的Lagrangian-Eulerian）形式在不可压缩的情况下，但是这些方法很难在每个时间步骤中重新生成网格，而在界限上移动。另一方面，主管调查员提出的移动坐标方法是解决难度。该研究项目的目的涵盖了两个意图：一个是将统一的派生派生为具有分别存在的移动边界的数值流量的管理方程式，并将科学前景赋予该领域；另一个是扩展啤酒方法和一般用途的移动坐标方法，将它们应用于物理和工程问题，并能够解决无法解决的问题，因为在20财年中的困难中，在20财政年度中有上述困难……更多的00…表明数值方法的管理方程，包括移动界限，即仲裁的coarter and inte inte and。移动坐标形式是按照此顺序统一得出的，并且仅在分析上应满足的几何保护定律的含义。此外，将移动坐标方法扩展为一般用途，并以每种方式和流量应用于两种情况：对于在弹道范围内发射的飞行弹丸的不稳定流量的〓〓lti域问题，以及用于弹道范围的单域问题，带有切割方法的单域问题，用于在高电量气电气电流电气电路的开放过程中用于分支流的切割方法。结果，已经证实了移动坐标方法有效地工作。在2001财政年度，将ALE形式扩展到通用坐标系，并应用于枪支肺泡流。在数值计算中，有两个课程：模拟复杂的流动更接近真实现象并获取细节，并建模（简化）并以较少的计算时间获得实用信息。作为后者课程的一个例子，准二维的欧拉方程，包括不仅有空间和时间的跨区域变化，还可以得出时间，并且与活塞运动的建模和压力损失一起正确应用了啤酒方法。通过与实验进行比较，已经证实了扩展的啤酒方法效果很好。在2002财年，获得的结果直到那时已发表在国际期刊上，并添加了评估和考虑。作为未来发展的准备阶段，已开发了用于任意配置和高准确方案（包括源术语）的非结构化网格求解器。