裂紋齒輪—轉(zhuǎn)子系統(tǒng)振動(dòng)特性分析
發(fā)布時(shí)間:2018-04-26 16:34
本文選題:齒根裂紋 + 嚙合剛度 ; 參考:《東北大學(xué)》2014年碩士論文
【摘要】:齒輪副是機(jī)械設(shè)備中最為常用的動(dòng)力和運(yùn)動(dòng)傳遞裝置,其力學(xué)行為和工作性能直接影響著機(jī)械系統(tǒng)的整體性能和可靠性。由于齒輪的受力情況相當(dāng)復(fù)雜,即使精細(xì)設(shè)計(jì)的齒輪箱也難免出現(xiàn)故障,這種不期望的故障可能導(dǎo)致嚴(yán)重的經(jīng)濟(jì)損失甚至危及生命,因而對(duì)齒輪的早期故障特征進(jìn)行分析并盡早識(shí)別齒輪早期故障具有重要的工程意義。本文以一個(gè)試驗(yàn)臺(tái)齒輪轉(zhuǎn)子系統(tǒng)為研究對(duì)象,建立齒輪副嚙合模型及齒輪轉(zhuǎn)子系統(tǒng)有限元模型,探討齒根裂紋故障對(duì)齒輪嚙合剛度和系統(tǒng)振動(dòng)響應(yīng)的影響,并通過(guò)試驗(yàn)對(duì)理論結(jié)果進(jìn)行分析和對(duì)比。論文的主要研究?jī)?nèi)容如下:(1)對(duì)嚙合剛度的三種求解方法,即變形法、能量法和有限元法進(jìn)行詳細(xì)的介紹,在傳統(tǒng)能量法求嚙合剛度的基礎(chǔ)上提出改進(jìn)能量法。通過(guò)變形法、改進(jìn)能量法和有限元三種嚙合剛度求解方法的對(duì)比表明,有限元法可以考慮更多的實(shí)際因素,計(jì)算結(jié)果較為準(zhǔn)確,但計(jì)算效率較低。傳統(tǒng)的能量法將輪齒視為基圓上的懸臂梁,在輪齒較多或較少時(shí)會(huì)產(chǎn)生很大的誤差,而改進(jìn)能量法考慮了真實(shí)的齒根過(guò)渡曲線,將輪齒視為齒根圓上的懸臂梁,更加符合輪齒的形狀和受力情況,計(jì)算結(jié)果更為準(zhǔn)確。(2)考慮較為真實(shí)的裂紋擴(kuò)展路徑和齒根裂紋對(duì)輪齒有效厚度的削弱作用,求解含齒根裂紋的齒輪嚙合剛度,分析了裂紋深度、寬度、起始位置和擴(kuò)展方向?qū)X輪嚙合剛度的影響。研究結(jié)果表明,采用直線來(lái)模擬裂紋的擴(kuò)展路徑是合理的;在裂紋深度較大時(shí)應(yīng)采用拋物線作為裂紋對(duì)輪齒有效厚度削弱的限制線。隨著裂紋深度和寬度的增加,嚙合剛度的降低幅度增加;隨著裂紋起始位置角的增大,嚙合剛度的降低幅度減小;隨著裂紋擴(kuò)展方向角的增大,嚙合剛度先減小后增大。(3)探討了齒根裂紋前后系統(tǒng)振動(dòng)響應(yīng)的變化以及不同裂紋參數(shù)對(duì)系統(tǒng)振動(dòng)響應(yīng)的影響。研究結(jié)果表明,裂紋出現(xiàn)后系統(tǒng)振動(dòng)響應(yīng)發(fā)生變化,時(shí)域波形中出現(xiàn)了以裂紋齒輪轉(zhuǎn)動(dòng)周期為間隔的周期性沖擊,在嚙合頻率及其諧波附近出現(xiàn)邊頻,并且沖擊、邊頻以及統(tǒng)計(jì)量的幅值隨著裂紋深度和寬度的增加而增大,隨裂紋起始位置角的增大而減小,隨裂紋擴(kuò)展方向角的增大先增加后減小。(4)考慮由輪齒彈性變形導(dǎo)致的延長(zhǎng)嚙合效應(yīng),基于有限元模型,分析了延長(zhǎng)嚙合對(duì)齒輪嚙合剛度和系統(tǒng)振動(dòng)響應(yīng)的影響。分析結(jié)果表明,考慮延長(zhǎng)嚙合效應(yīng)后,單雙齒交替時(shí)嚙合剛度不再是突變的而是漸變的,并且隨著扭矩的增大,延長(zhǎng)嚙合現(xiàn)象越來(lái)越顯著。另外,考慮延長(zhǎng)嚙合效應(yīng)后,系統(tǒng)振動(dòng)響應(yīng)的時(shí)域和的頻域特征也發(fā)生改變。(5)通過(guò)實(shí)驗(yàn)對(duì)理論分析進(jìn)行驗(yàn)證,尋找有效識(shí)別早期裂紋故障的方法。研究表明,裂紋出現(xiàn)后,實(shí)驗(yàn)和仿真信號(hào)的瞬時(shí)能量在時(shí)間分布上產(chǎn)生周期性沖擊,并且隨著裂紋深度的增加,沖擊能量的幅值越來(lái)越大。因而,通過(guò)Hilbert瞬時(shí)能量的變化可以較為輕松的檢測(cè)齒輪裂紋故障。
[Abstract]:Gear pair is the most commonly used power and motion transmission device in mechanical equipment, its mechanical behavior and working performance directly affect the overall performance and reliability of the mechanical system. Because the force condition of the gear is quite complex, even the fine design gear box is unavoidable to fail, this undesirable failure may lead to a serious economy. The loss even endangers life, so it is of great engineering significance to analyze the early fault characteristics of the gear and identify the early fault of the gear as early as possible. In this paper, a gear rotor system of a test rig is used as the research object, the gear pair meshing model and the finite element model of the gear rotor system are set up, and the tooth root crack fault on the gear meshing stiffness is discussed. The main research contents of the thesis are as follows: (1) the three methods of solving meshing stiffness, namely, deformation method, energy method and finite element method, are introduced in detail, and the improved energy method is put forward on the basis of the traditional energy method to find the meshing stiffness. The comparison of the three methods of solving the meshing stiffness of the improved energy method and the finite element method shows that the finite element method can consider more practical factors, the calculation result is more accurate, but the calculation efficiency is low. The traditional energy method regards the tooth as the cantilever beam on the base circle, and it will produce great error when the tooth is more or less, and the improved energy method is improved. Considering the true tooth root transition curve, the tooth is regarded as the cantilever beam on the tooth root circle, and the calculation results are more accurate. (2) considering the more true crack propagation path and the tooth root crack to weaken the effective thickness of the tooth, the meshing stiffness of the teeth with the tooth root crack is solved, and the crack is analyzed. The effect of depth, width, starting position and extension direction on the gear meshing stiffness. The results show that it is reasonable to use a straight line to simulate the propagation path of a crack; a parabola should be used as a limiting line to weaken the effective thickness of the tooth when the crack depth is large. With the increase of the crack depth and width, the meshing stiffness is reduced. The reduction of the meshing stiffness decreases with the increase of the starting angle of the crack, and the meshing stiffness decreases first and then increases with the increase of the direction angle of the crack growth. (3) the changes of the system vibration response before and after the tooth root crack and the effect of the different crack parameters on the system vibration response are discussed. The results show that the crack is out of the crack. The vibration response of the system is changed. The periodic impact of the crack gear rotation period appears in the time domain, and the edge frequency occurs near the meshing frequency and its harmonics, and the amplitude of the shock, the side frequency and the statistics increase with the increase of the crack depth and width, and decreases with the increase of the initial angle of the crack. The increase of the direction angle of the crack growth first increases and then decreases. (4) considering the extended meshing effect caused by the elastic deformation of the tooth, the effect of the extended meshing on the gear meshing stiffness and the vibration response of the system is analyzed based on the finite element model. The results show that the meshing stiffness of the single and double teeth alternation is no longer abrupt when the engagement effect is extended. It is a gradual change, and with the increase of torque, the prolonged meshing phenomenon becomes more and more obvious. In addition, the time-domain and frequency domain characteristics of the vibration response of the system are also changed after considering the prolongation of the meshing effect. (5) through the experiment, the theoretical analysis is verified to find a method to effectively identify the early crack failure. The study shows that after the crack appears, the experiment is shown. The instantaneous energy of the simulated signal produces a periodic impact on the time distribution, and the amplitude of the impact energy increases with the increase of the depth of the crack. Therefore, the fault of the gear crack can be easily detected by the change of the instantaneous energy of the Hilbert.
【學(xué)位授予單位】:東北大學(xué)
【學(xué)位級(jí)別】:碩士
【學(xué)位授予年份】:2014
【分類(lèi)號(hào)】:TH113.1
【相似文獻(xiàn)】
相關(guān)期刊論文 前10條
1 程國(guó)明;鄭耘;;對(duì)齒輪材料的研究[J];消費(fèi)導(dǎo)刊;2010年08期
2 М.П.НОВИКОВ ,程┌,
本文編號(hào):1806796
本文鏈接:http://sikaile.net/kejilunwen/jixiegongcheng/1806796.html
最近更新
教材專(zhuān)著