The development of solution methods on electro-magnetic fields, sound fields and related coupled systems by means of domain decomposition method and optimization theory

本研究项目旨在发展解决方法，以分析环境问题中产生的复杂现象，人体液体的流动。(1)河田秀夫（Hideo Kawarada）等人提出的多相流分布理论方法（DTAMF），分析了相间边界上相互作用的多相流，有效地计算了滩涂附近的流动问题，包括滩涂和泥土中的空气流动、滩涂和泥土中的海水流动、滩涂和泥土中的溢油流动。特别值得注意的是，利用DTAMF的结果模拟了细菌对溢油的分解和溢油在沙滩上的粘附现象。DTAMF也被应用于分析液体流过脊髓附近复杂结构的运动。(2)广岛大学课题组从环境实验的角度讨论了海岸带生态系统中沙滩或潮滩边缘波浪对海水的影响对物种生存的影响。我们试图通过建立一个将破碎波与生态系统动力学联系起来的数学模型来解释这一实验结果，其中相场模型和遗传算法发挥了重要作用。基于这一思想进行了数值模拟。

This research project intended to develop solution methods to analyze complex phenomena arising in environmental problems, flow of liquids in human body.(1)The Distribution Theoretic Approach to Multi-phase Flow (DTAMF) developed by Hideo Kawarada and his collaborators to analyze multi-phase flow interacting each other at the boundary between phases, which was effectively used to compute the flow problems arising in the neighborhood of tidal flats including the flows of air on the beach and in the earth, sea water on the beach and in the earth, and spilled oil on the beach and in the earth. Especially it should be noted that decomposition of spilled oil by bacteria and adhesive phenomena of oil on a sandy beach were simulated by use of the results obtained in DTAMF. DTAMF was also applied to analyze the motion of liquids to flow through complex structure near the spinal cord.(2)The role of waves at margins of sandy beach or a tidal flat to sea water for determination of species survival in a coastal ecosystem was discussed from a view point of environmental experiments by the group of Hiroshima University. We tried to interpret this experimental result by constructing a mathematical model connected with breaking waves and ecosystem dynamics, in which a phase field model and genetic algorithm played important roles. The numerical simulation was done due to this idea.