摘 要
JS400ATV發(fā)動(dòng)機(jī)是建設(shè)工業(yè)集團(tuán)生產(chǎn)的沙灘越野摩托車裝配的發(fā)動(dòng)機(jī)，該車主要出口歐美國家，但就其的通過噪聲較大，經(jīng)道路通過噪聲實(shí)驗(yàn)，發(fā)現(xiàn)該發(fā)動(dòng)機(jī)噪聲是該車型的主要噪聲源，且初步發(fā)現(xiàn)該發(fā)動(dòng)機(jī)的曲軸箱殼體在運(yùn)行過程中存在共振現(xiàn)象，為進(jìn)一步證實(shí)該機(jī)曲軸箱殼體存在共振，有必要對該曲軸箱進(jìn)行理論模態(tài)分析，為此需要對該曲軸箱殼體進(jìn)行三維建模。目前，工程上主流建模軟件建模軟件為Catia，UG NX，Pro/Engineer，Solidworks等。我建此模型選用Pro/Engineer。由二維圖紙分析，該曲軸箱體主要是殼體，其余為加強(qiáng)筋，柱體，孔等。殼體部分主要是有多個(gè)曲面相交。除了草圖外，常用的命令為拉伸，挖孔，增厚，倒圓角，掃描，拔模，修剪，混合，合并，偏置等命令。通過對該曲軸箱模型的建立，可以使自己掌握模型建立的基本過程和方法，為并為下一步的仿真分析打下基礎(chǔ)。
對殼體進(jìn)行模態(tài)分析，理論模態(tài)分析過程中用ANSA進(jìn)行幾何清理。再導(dǎo)入MSC.PATRAN /NASTRAN進(jìn)行定義和計(jì)算而得到。實(shí)驗(yàn)?zāi)B(tài)和理論模態(tài)作比較。
關(guān)鍵詞：曲軸箱，殼體，三維建模，Pro/Engineer，模態(tài)分析







ABSTRACT
The JS400ATV engine is assembled on beach cross-country motorcycle produced by JianShe industry group. It mainly exports to Europe and the United States. But there’s a bit of yawp when ridded. We found out that the engine noise is the main noise source analyzed by riding experiment and there is resonance phenomenon in its crankcase carapace when running. To prove the resonance in crankcase carapace, it is necessary to make its 3D-model. At present, the primary 3D-models for engineering are Catia，UG NX，Pro/Engineer，Solidworks and so on .Because of powerful function in CAD，CAE，CAM and integrate design, analysis, manufacture, it’s popular among design company and it is being used in Machine, automobile, shipbuilding and aviation industry. I choose Pro/Engineer to make 3D-model. Knowing from 2D- drawing, the crankcase mostly consists of carapace plus rib, pillar, hole and so on. The carapace is intersected and thickened by many surfaces. Except drawing, the common orders are “pad”,“hole”,“thicksurface”,“edgefilet”,“sweep”,“split”,“trim”,“union trim”, “offset” and so on. I come to master the basic ways and process to build 3D-Model by building this model, and set up the base for emulator.
ANSA is used to pretreat the model on the theoretic modal analysis,and then import to the MSC.PATRAN / NASTRAN to defined and calculat.thus we gain modal analysis results. At last,we compare the results between the theoretic modal analysis and experiment modal analysis.
Key words：crankcase, shell part ，3D-model, modal analysis，Pro/Engineer

目錄
摘 要 I
ABSTRACT II
目錄 III
1 緒 論 1
1.1研究的背景及其意義 1
1.2國內(nèi)外建模的主要工具和現(xiàn)狀 2
1.3 PRO／ENGINEER功能模塊介紹 4
1.4 MSC.NASTRAN簡介及應(yīng)用 14
1.5主要研究內(nèi)容和曲軸箱建模方法 14
1.6本章小結(jié) 15
2 右曲軸箱殼體模型的建立 16
2.1主殼體部分的建立 16
2.1.1創(chuàng)建主體拉伸 17
2.1.2通過拉伸創(chuàng)建突臺(tái)部分 22
2.1.3創(chuàng)建突臺(tái) 23
2.2孔槽部分的建立 25
2.3抽殼和拔模 28
2.4創(chuàng)建其他結(jié)構(gòu) 31
2.4.1創(chuàng)建突臺(tái)的結(jié)構(gòu) 31
2.4.2創(chuàng)建裝配孔 33
2.4.3創(chuàng)建曲軸箱內(nèi)部結(jié)構(gòu) 35
2.4.創(chuàng)建下圖結(jié)構(gòu)，其二維視圖如下 36
2.4.5創(chuàng)建一個(gè)拉伸 37
2.4.6創(chuàng)建下邊視圖的結(jié)構(gòu) 37
2.4.7拉伸裝配孔 38
2.4.8曲軸箱內(nèi)部的結(jié)構(gòu) 40
2.4.9創(chuàng)建加強(qiáng)筋結(jié)構(gòu) 41
2.4.10再構(gòu)建一個(gè)加強(qiáng)筋 45
2.4.11建立裝配的拉伸 47
2.5突臺(tái)機(jī)構(gòu) 48
2.6現(xiàn)在構(gòu)建一個(gè)油道 52
2.12本章小結(jié) 57
3．右曲軸箱蓋模態(tài)分析 58
3.1右側(cè)變速器箱蓋理論模態(tài)分析 58
3.2右側(cè)變速器箱蓋實(shí)驗(yàn)?zāi)B(tài)分析 60
3.3本章小結(jié) 64
致 謝 65
參考文獻(xiàn) 66