本文主旨在於探討汽車車門於關閉過程產生的振動與噪音。主要分成了實驗與模擬分析兩部分。實驗方面，從簡單懸臂樑、無矽膠之簡化模型、含矽膠之簡化模型，最後則是實車試驗以此循序漸進。因本實驗室無所謂的無音室或半無音室，因此於噪音測試則是依據國家標準(CNS7183)進行背景噪音修正，且於實驗前利用B&K type 3541校正器進行較正確定實驗之正確性。最初以一衝擊槌敲擊一鋁製懸臂樑探討其振動造成之噪音。簡化模型主要是依據實車包含車門、車體及密封系統來簡化，並針對關門角度三十度和六十度及含矽膠與否進行測試；另外也針對實驗所使用之矽膠條依據國家標準(CNS3553)進行拉伸試驗。實車試驗則包含了車門關閉實驗與模態實驗，經由此兩實驗，發現車門對車體造成的衝擊其頻率與頂棚之自然頻率接近而造成共振效應，因此於設計減少車門關閉時所產的振動與噪音時應考慮此因素。
本文採用商用有限元素軟體LS-DYNA進行數值模擬分析，而Arbitrary Lagrangian-Eulerian(ALE)方法，則有效用於模擬物體振動產生之聲壓，並依據實際條件及實驗獲得之數據給予初始負載，且於振動之結構體周圍以空氣網格包覆，以模擬流固耦合(Fluid Structure Interaction, FSI)現象，所有模擬皆以實際實驗條件與情況進行分析。
由試驗與模擬結果得知，懸臂樑與簡單模型其差別為真實物體接觸與否，因此於模擬聲壓時需將接觸條件納入考慮；而簡單模型包括含矽膠條與不含矽膠條其模擬之聲壓位準結果與實驗值差距在二十分貝以下，加速度響應誤差值則在15％以下，此一系列驗證指出於模擬汽車車門產生之聲壓與振動可採用此方法進行分析。本文最後建立一近似之汽車模型與實驗進行比較，其模擬結果雖與實驗有一段差距，但可預期倘若能以完整之幾何進行分析應能獲得較好之結果。

The purpose of this study is to investigate automotive side door closing process induced noise and vibration. This thesis is divided into two parts: experimental measurement of sound and vibration and the numerical simulation.
In experimental aspect, there are three types including cantilever beam, simplified model and real car. Because there is no anechoic or hemi-anechoic room in our laboratory, the Chinese National Standards 7183 of environmental noise correction has been used. Before testing, a Brüel & Kjær (B&K) sound intensity calibrator is being used to calibrate testing microphones. A cantilever beam is used to test the noise and vibration response under impact. A closing angle of 30 degree and 60 degree are set in the simplified model test. A real car test model involves door closing and experimental modal analysis. Upon mentioned, a resonance effect happened due to that impact frequency is near roof’s natural frequency. For this reason, a designer must pay attention to this factor.
A commercial software LS-DYNA is used to simulate the model. Arbitrary Lagrangian-Eulerian method is effective to simulate sound pressure. All the vibrating structures are covered with air mesh to simulate fluid-structure-interaction. Every simulation is under true environment and conditions.
From results, the difference between cantilever beam and simple box is contact. It is important to consider contact condition during simulation. The simulation results of simple box are under 20 decibel. Acceleration error is under 15 percent. It is feasible to simulate side door closing process induced noise and vibration depends on those verifications. A similar model of real car is utilized to compare with experiments. Although the error is large, the simulation results would be better if we could get real shape and material of car.

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