【摘要】：國內外的統(tǒng)計數(shù)據顯示，工程中疲勞破壞占機械設備所發(fā)生破壞的比例達60%~90%，可見疲勞為機械結構最常見的失效形式。在空氣壓縮機中，增速斜齒輪副連接發(fā)動機和葉輪，是空氣壓縮機中的一個關鍵部件，其使用壽命決定了整機的無故障工作時間。傳統(tǒng)的設計往往基于靜強度設計方法，采用加大許用安全系數(shù)或降低許用應力的方法來提高其可靠性，往往不能保證其運行的可靠性和安全性。斜齒輪副主要承受循環(huán)載荷，一旦發(fā)生疲勞失效、斷齒故障，不但影響設備的正常運轉，而且?guī)聿恍〉慕洕鷵p失。因此，根據齒輪副的工作條件做出準確的受力分析，得出其所受應力應變情況、掌握破壞規(guī)律、估算其疲勞壽命是十分必要的，，同時也可以為空氣壓縮機的檢查、維修、保養(yǎng)等提供必要的數(shù)據。 為此，本文以空氣壓縮中的增速斜齒輪副為對象綜合運用彈性接觸有限元理論、齒廓修形理論、多體動力學理論、疲勞損傷理論及模態(tài)分析理論，分別對齒輪副進行靜強度分析、齒廓修形、動力學仿真、疲勞壽命預測及模態(tài)分析，對空氣壓縮機的抗疲勞設計具有較大的參考價值。本文研究工作包括如下幾個方面： ①在ANSYS中建立齒輪副的多齒嚙合有限元模型并加載求解，求得嚙合過程中的應力分布，并對齒頂出現(xiàn)嚙合沖擊的情況采取齒廓修形以改善輪齒受力，最后研究了摩擦系數(shù)、修形量對齒頂應力峰值的影響情況。研究結果表明：修形后齒輪的最大應力為236.223MPa，采用齒廓修形有效地降低了齒頂出現(xiàn)的嚙合沖擊現(xiàn)象。最大應力有隨摩擦系數(shù)和修形量的增加而降低的趨勢。 ②在動力學分析軟件ADAMS里面建立斜齒輪副的虛擬樣機模型，兩齒輪之間添加碰撞，求得動態(tài)嚙合力，并將其與理論計算值比較，結果表明：嚙合力的理論計算值與仿真計算值誤差約5%，可以為疲勞分析提供載荷譜。 ③根據材料的性能，擬合材料的近似S-N曲線，并結合應力結果、載荷譜基于疲勞損傷理論預測斜齒輪副的疲勞壽命，結果表明：齒輪副的安全系數(shù)均大于1，忽略極少數(shù)對齒輪的整體壽命影響較小的低壽命點，可達到64.17年，大于設計要求的20年使用壽命，且有很大富裕。最后研究了表面粗糙度、載荷對齒輪疲勞壽命的影響情況。 ④對斜齒輪副進行模態(tài)分析，求得其前6階固有頻率和相應振型。結果表明：齒輪副嚙合頻率為6078.25Hz遠大于前6階固有頻率，且基頻大于主從動輪的轉頻，所以系統(tǒng)在運行過程中不會發(fā)生共振，具有良好的動態(tài)特性。
[Abstract]:The statistics at home and abroad show that the proportion of fatigue damage to mechanical equipment in engineering is 6090. It can be seen that fatigue is the most common failure form of mechanical structure. In the air compressor, the speed increase helical gear pair connects the engine and the impeller, which is a key component in the air compressor. Its service life determines the fault-free working time of the whole machine. The traditional design is often based on static strength design method, the method of increasing allowable safety factor or reducing allowable stress is adopted to improve its reliability, which can not guarantee its reliability and safety. The helical gear pair is mainly subjected to cyclic load. Once fatigue failure and broken tooth failure occur, not only the normal operation of the equipment is affected, but also the economic loss is not small. Therefore, according to the working conditions of the gear pair, it is very necessary to make an accurate force analysis, to obtain the stress and strain situation, to master the failure law, to estimate its fatigue life, and to inspect and maintain the air compressor at the same time. Provide necessary data such as maintenance. Therefore, in this paper, the elastic contact finite element theory, tooth profile modification theory, multi-body dynamics theory, fatigue damage theory and modal analysis theory are applied to the helical gear pair in air compression. The static strength analysis, tooth profile modification, dynamic simulation, fatigue life prediction and modal analysis of gear pairs are of great reference value to the anti-fatigue design of air compressor. The research work in this paper includes the following aspects: 1 the finite element model of multi-tooth meshing of gear pair is established in ANSYS, and the stress distribution in meshing process is obtained by loading and solving. In order to improve the force of gear teeth, the influence of friction coefficient and shape modification on the peak stress of tooth top is studied. The results show that the maximum stress of the modified gear is 236.223 MPa, and the tooth profile modification can effectively reduce the meshing impact phenomenon at the top of the gear. The maximum stress tends to decrease with the increase of friction coefficient and shape modification. (2) the virtual prototype model of helical gear pair is established in the dynamic analysis software ADAMS. The dynamic meshing force is obtained by adding collision between the two gears, and the dynamic meshing force is compared with the theoretical calculation value. The results show that the error between the calculated and simulated values of the meshing force is about 5, which can provide the load spectrum for fatigue analysis. (3) according to the properties of the material, fitting the approximate S-N curve of the material and combining with the stress result, the fatigue life of the helical gear pair is predicted by the load spectrum based on the fatigue damage theory. The results show that the safety factor of the gear pair is more than 1. A few low life points which have little influence on the overall life of gears are neglected, which can reach 64.17 years, which is larger than the 20 years' service life required by the design, and has a lot of affluence. Finally, the influence of surface roughness and load on the fatigue life of gear is studied. (4) the modal analysis of helical gear pair is carried out, and the first 6 natural frequencies and corresponding modes are obtained. The results show that the meshing frequency of gear pair is much larger than the first 6 natural frequency and the fundamental frequency is larger than the rotation frequency of the master-slave wheel, so the system will not resonate during the running process and has good dynamic characteristics.
【學位授予單位】：重慶大學
【學位級別】：碩士
【學位授予年份】：2013
【分類號】：TH452;TH132.4

【參考文獻】

相關期刊論文 前10條

1 符雙學;田巍;李長云;;基于有限元法的齒輪強度接觸分析[J];長沙航空職業(yè)技術學院學報;2009年02期

2 尹剛;;高重合度齒輪應力場有限元分析[J];重慶大學學報;2010年07期

3 林騰蛟;沈亮;趙俊渝;;風電增速箱輸出級齒輪副疲勞壽命有限元分析[J];重慶大學學報;2012年01期

4 閻樹田;梁繼斌;沙成梅;喬偉峰;;精確模型下斜齒輪接觸應力的有限元分析[J];蘭州理工大學學報;2006年03期

5 王哲;胡迎鋒;;齒輪建模與接觸應力分析[J];湖北工業(yè)大學學報;2006年03期

6 龍凱,程穎;齒輪嚙合力仿真計算的參數(shù)選取研究[J];計算機仿真;2002年06期

7 馬雪潔;謝剛;王小林;;基于ANSYS/LS-DYNA的準雙曲面齒輪動力學接觸仿真分析[J];機械傳動;2005年06期

8 徐穎強,趙寧,呂國志;航空硬化齒輪材料力學性能研究[J];機械科學與技術;2002年04期

9 唐進元;蒲太平;;加載螺旋錐齒輪接觸軌跡變化規(guī)律的研究[J];機械科學與技術;2010年04期

10 曹萍;王衛(wèi)英;;微型客車車身疲勞壽命有限元分析[J];機械科學與技術;2012年04期

本文編號：2410409