Design optimization of composite structures composed of dissimilar materials in flow induced vibration problem and its application to lure design

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K03819
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18030:Design engineering-related
• Research Institution: Komatsu University
• Principal Investigator: SHI JINXING 公立小松大学, 生産システム科学部, 准教授 (30744669)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 構造最適設計 / 流体励起振動 / 異種材料複合構造体 / ルアー / 数値解析

Outline of Final Research Achievements

In this study, we focused on the flow-induced vibration (FIV) problem and developed a new structural design optimization method for composite structures composed of dissimilar materials. First, employing weakly coupled fluid-structure interaction analysis, we replicated the FIV of composite structures, using vibration lures and jig head soft lures as design examples. Next, in the structural design optimization, the response surface based on Latin Hypercube Sampling and RBF network was created using the analytical results. Then, to improve the accuracy of the optimal solution while searching the global response surface, sparse regions in the design variable space and the minimum value in the response surface are set as new sample points using a density function. Hence, the response surface was updated sequentially. The results of design examples show that the proposed structural design optimization method can minimize the objective function successfully.

Free Research Field

設計工学、計算力学、材料力学

Academic Significance and Societal Importance of the Research Achievements

流体励起振動は土木、建築、機械、航空、船舶、原子力などのあらゆる分野で発生するため、構造の性能・信頼性設計に避け通ることのできない重要な課題である。しかし、乱流と振動の複合現象の複雑さのため、それに対応可能な構造最適設計手法の開発は大きく立ち遅れている。本研究では、既存の構造最適設計手法の適応が難しい流体－構造連成解析を着目し、流体励起振動問題における異種材料複合構造体の新たな構造最適設計手法を開発した。一方、市販の釣りルアーは設計者の経験と勘のみで設計され、振動不足など問題がある。そこで、実用例として、最適な流体励起振動が表現可能なルアーの構造設計を行い、釣果の向上を図ることができた。