點焊對振動與碰撞之模擬與優化

Spot Weld Simulation and Optimization for Vibration and Crashworthiness

陳慶宗(Ching-Tzung Chen)

指導教授 ： 黃秀英

國立臺北科技大學/機電學院/車輛工程系所/碩士(2009年)

https://doi.org/10.6841/NTUT.2009.00446

摘要

對車體結構設計而言，結構輕量化與降低生產成本是目前熱門研究方向，因此結合往年累積的經驗，應用CAD(Computer Aide Design)與CAE(Computer Aide Engineering)是目前較常使用的設計方式。隨著現今科技的進步，有越來越多的接合方法應用於車體結構上，如電阻點焊、雷射點焊以及鉚釘等等。

本論文是針對點焊做振動與碰撞模擬分析與優化，研究中以MSC/PATRAN為前後處理器，MSC/NASTRAN為NVH之分析與優化求解器，MSC/DYTRAN為碰撞安全之求解器，進行點焊個數的最佳化分佈。在NVH之優化方面，以一簡單直線型樑為範例，利用六種建模法來模擬點焊的連結強度，分別為共點建模法、CELAS建模法、CBAR建模法、Rigid Element 建模法、CWELD建模法以及Area Contact建模法，比較參考文獻之實驗結果，在NVH方面以CELAS建模法為最接近實驗值，將直線型梁點焊對NVH最佳化後可以順利減少20%的點焊數目。

在碰撞安全方面不考慮結構體積變化，比較點焊變形能量，進而最佳化點焊的數目，在點焊未破壞的情況下，可以順利減少40%的點焊個數。若不變更點焊個數，重新分配點焊間距，可使點焊較平均吸收碰撞能量。

關鍵字

點焊 ； 點焊模擬 ； 點焊最佳化 ； 最佳化 ； 能量吸收 ； 碰撞安全 ； 振動

並列摘要

Reducing the design cycle time and product cost with light weight is one of the main focus in the auto industry. To provide efficient design, Computer Aided Design (CAD) and Computer Aided Engineering (CAE) were used.

The objective of the study is to use CAE and optimization to design a better spot weld pattern. In the study, MSC/PATRAN, NASTRAN and DYTRAN were used. Six different spot weld modeling schemes were developed. The analysis results were compared with the experiment data. The best correlated CAE model was used for the vibration, and impact optimization. Based on the optimization results, design concept were proposed for different practical applications.

In the study, different spot weld modeling were developed. It showed good correlation with the testing data. A new topology design optimization using user’s defined function built in MSC/NASTRAN was developed. The optimization results provide effective design guidance for the industry applications.

並列關鍵字

Spot Weld ； Optimization ； Energy Absorption ； Crashworthiness ； Vibration

參考文獻

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