摘要:隨著汽車工業的發展，汽車制造商除了關注汽車的安全性、舒適性外，同時為 了節約能耗，適應嚴格的排放標準，保護環境，不得不采用更薄的鋼板作為汽車的 外覆蓋件，從而導致外覆蓋件“變軟”，產生一系列問題，如外覆蓋件自重或者輕微 的碰撞引起的凹陷，汽車行駛中產生的振動、噪音等等。所謂汽車板材抗凹性是指 經一定變形的試件或者局部凹陷變形，保持形狀的能力。其包括抗凹剛度，起伏載 荷和局部凹陷抗力 3 個指標[1] 。

汽車開閉件的屈曲抗凹分析是衡量汽車開閉件穩定性的一種方法,由于開閉件外板本身的形狀確定了其結構具有不穩定的特性,所以了解其屈曲的性能就顯得尤 為重要;通過有限元分析確定其性能并改進開閉件設計使其達到抗凹性能的要求。

　　　本人在查閱大量文獻和已有試驗結果的基礎上，通過 SolidWorks 建模模擬汽 車引擎蓋，再運用有限元分析軟件 ANSYS 對引擎蓋進行屈曲抗凹分析，包括以下 主要內容：

(1)簡化引擎蓋模型，運用 SolidWorks 建模。

（2）得出邊界條件并施加載荷，運用 ANSYS 對引擎蓋進行屈曲抗凹分析。

（3）對結果對比分析并總結。

（4）優化設計，對引擎蓋進行加筋并進行對比分析。

關鍵詞:  有限元，屈曲，開閉件（引擎蓋），ANSYS

Abstract:As the car industry, automobile maker in addition to the attention of the security, comfort, but to save energy consumption, to strict standards, environmental protection have to adopt a thin steel as the outer cover, which led to outer cover a "soft", a series of questions, such as the outer covering a feeling or a slight collision cause depression, the car in the vibration, noise, etc. The car to the board was to be tried by the shape of a concave shape or local, in place. it consists of resistance, the stiffness of the loading and local hollow resistance three indicators. 

　　　Buckling and denting analys is of the closures is a method to evaluate the stability of structure.For the instability caused by the figure of out-panel,it is important to know about the buckling and denting performance of out-panel. The analys is of finite element can help to confirm its performance and improve its design to meet the needs of denting requirements.

　　　Myself  in  the  consult  massive  literature  and  had  in  the  test  result  foundation, through the SolidWorks modelling simulation automobile bonnet, carries on the flexure anti-concave analysis again using finite element analysis software ANSYS to the bonnet, including the following primary coverage:

(1) The simplified bonnet model, utilizes the SolidWorks modelling.

(2)  Obtains  the  boundary  condition  and  exerts  the  load,  carries  on  the  flexure anti-concave analysis using ANSYS to the bonnet.

(3) To analyzes the result subtotal.

(4)  The  optimization  design,  carries  on  to  the  bonnet  reinforces  and  carries  on  the contrastive analysis.

Keyword: FEM,buckling,closures,ANSYS