Identification of error factors between actual system and finite element model using the transient response of structural acoustic coupled system

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K04018
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 20010:Mechanics and mechatronics-related
• Research Institution: Gifu University
• Principal Investigator: FURUYA Kohei 岐阜大学, 工学部, 准教授 (40580056)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 過渡応答 / 相互平均コンプライアンス / 有限要素法 / CAE / 振動騒音

Outline of Final Research Achievements

In this research, the novel approach which uses transient response instead of the frequency response to identify error factors between actual system and finite element model has been proposed. A frequency response is calculated from time domain response which includes reflection waves from entire system. Accordingly, it is difficult to identify error factors. On the other hands, the transient response measured immediately after excitation includes reflection waves from local components only. Therefor it is easy to identify error factors than using frequency response. Technical novelties of this research are, using transient response to identify the error factors in structural acoustic coupled system, using time domain mutual mean compliance to determine the contribution of components to the transient response, and using time domain panel contribution analysis. The effectiveness of the proposed approach was shown in the structural acoustic coupled system.

Free Research Field

機械力学

Academic Significance and Societal Importance of the Research Achievements

従来は乖離要因を特定する際に周波数応答を利用することが多かった．周波数応答は励起された時刻歴応答が収束するまでの波形をフーリエ変換して求めるため，系全体の影響が含まれる．よって周波数応答から，乖離要因がどこにあるのかを確実に特定することは困難であった．本研究では過渡応答，特に加振直後の加振点近傍の応答には系の局所的な影響のみが含まれることに着目した点に学術的特徴がある．過渡応答を実験と有限要素解析で比較することで，どこに乖離要因が存在するのかを特定できることを構造系単体，音響系単体，構造音響連成系で示した．また過渡応答に含まれる部品毎の影響を相互平均コンプライアンスで分離する方法を示した．