本文關(guān)鍵詞：大型懸掛式慣性振動設(shè)備若干關(guān)鍵問題研究　出處：《南京理工大學(xué)》2014年博士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 懸掛 慣性激振 高方平篩 柔性吊桿 幾何非線性 瞬態(tài) 減振 有限元

【摘要】：本文以大型懸掛式慣性振動設(shè)備——高方平篩為研究對象,針對其運(yùn)轉(zhuǎn)過程中出現(xiàn)的有害振動和結(jié)構(gòu)破壞,運(yùn)用非線性彈性力學(xué)理論、交流電機(jī)瞬態(tài)分析理論和數(shù)值模擬技術(shù)對高方平篩柔性吊桿非線性彈性特性、系統(tǒng)整體動力學(xué)特性、起動和停車多場耦合瞬態(tài)過程、結(jié)構(gòu)破壞原因和動態(tài)設(shè)計(jì)方法等關(guān)鍵問題進(jìn)行了深入的研究和探索。為高方平篩這類懸掛式振動機(jī)械的動態(tài)分析、有害振動抑制和慣性激振裝置設(shè)計(jì)提供理論依據(jù)。主要內(nèi)容如下： 1.針對大型懸掛式振動設(shè)備關(guān)鍵懸吊彈性部件——柔性吊桿的非線性彈性特性進(jìn)行了研究。建立了柔性吊桿軸向受力橫向大變形非線性梁力學(xué)模型。考慮梁軸線可伸長、大轉(zhuǎn)角和大變形導(dǎo)致的幾何非線性,并將力平衡方程建立在梁大變形的構(gòu)形基礎(chǔ)上,得到了軸向受力橫向大變形梁非線性微分控制方程組。通過數(shù)值模擬,分析了軸向力、橫向力和梁兩端邊界條件對梁變形的影響規(guī)律；得到了柔性吊桿自由端橫向和軸向變形非線性彈性特性曲線,為懸掛式振動設(shè)備的動力學(xué)建模提供理論基礎(chǔ)。 2.提出了剛?cè)狁詈系母叻狡胶Y系統(tǒng)動力學(xué)建模方法。分析了四組吊桿束變形運(yùn)動與篩體剛體運(yùn)動的幾何約束關(guān)系,建立了慣性振動設(shè)備的非線性動力學(xué)模型,給出了系統(tǒng)穩(wěn)態(tài)振幅和低階固有頻率的計(jì)算方法。采用有限元方法,對系統(tǒng)進(jìn)行了模態(tài)分析和動力學(xué)響應(yīng)分析,并對篩體穩(wěn)態(tài)運(yùn)轉(zhuǎn)狀態(tài)進(jìn)行了測試,實(shí)驗(yàn)結(jié)果驗(yàn)證了理論分析。 3.針對高方平篩在起動階段存在的共振現(xiàn)象,對采用自調(diào)式慣性激振方式的系統(tǒng)起動多場耦合瞬態(tài)過程進(jìn)行了研究�？紤]柔性吊桿束自由端橫向剛度非線性、異步電動機(jī)起動瞬態(tài)過程和滾動軸承摩擦,建立了系統(tǒng)起動瞬態(tài)過程的剛、柔、電多場耦合數(shù)學(xué)模型。分析了原激振方式下起動瞬態(tài)共振的產(chǎn)生、發(fā)展和衰減過程,揭示了自調(diào)式激振方式對起動瞬態(tài)共振的抑制機(jī)理。在深入分析自調(diào)式激振裝置各參數(shù)對起動瞬態(tài)共振影響基礎(chǔ)上,提出了一種新的剛度可變自調(diào)式慣性激振方式,該激振方式不但能進(jìn)一步減小起動階段最大瞬態(tài)振幅,還能降低減振效果對相關(guān)參數(shù)的敏感度,提高減振穩(wěn)健性。 4.針對高方平篩在停車階段存在的共振現(xiàn)象,對采用自調(diào)式慣性激振的系統(tǒng)停車瞬態(tài)過程進(jìn)行了數(shù)值模擬研究�？紤]異步電動機(jī)制動時(shí)機(jī)械特性,分析了原激振方式下停車瞬態(tài)共振的產(chǎn)生機(jī)理,揭示了自調(diào)式激振方式對停車瞬態(tài)共振的抑制機(jī)理和影響因素。研究了新型激振方式下系統(tǒng)停車瞬態(tài)過程,新型激振方式能同時(shí)使起動和停車階段瞬態(tài)共振獲得較好的抑制效果,為慣性振動機(jī)械瞬態(tài)共振的抑制提供了一種新思路。 5.對高方平篩的動強(qiáng)度和動態(tài)設(shè)計(jì)方法進(jìn)行了研究。采用有限元方法進(jìn)行了結(jié)構(gòu)動力學(xué)分析,找到了結(jié)構(gòu)破壞的主要原因。分析了若干因素對危險(xiǎn)位置應(yīng)力的影響,提出了改進(jìn)結(jié)構(gòu)強(qiáng)度的各種措施,這些措施和方法在合作單位工程實(shí)踐中被證明是行之有效的。分析了在高方平篩大型化發(fā)展中,更有利于保持較好動強(qiáng)度的結(jié)構(gòu)設(shè)計(jì)途經(jīng)。 通過上述關(guān)鍵問題研究,本文最終形成了一整套適應(yīng)高方平篩大型化和高可靠性的建模理論和動態(tài)設(shè)計(jì)方法。
[Abstract]:In this paper, the large hanging type inertial vibrating machine - high Fang Ping screen as the research object, aiming at the destruction of harmful vibration in the operation process and structure, using the nonlinear elastic theory of AC motor, the transient analysis theory and numerical simulation of nonlinear characteristics of high flexible suspender Fang Ping sieve, dynamic characteristics of whole system, start and stop the multi field the coupled transient process, in-depth study and exploration of key issues of structural damage reason and dynamic design method. For this kind of high Fang Ping sieve suspended vibration machine dynamic analysis, provide a theoretical basis for the design of harmful vibration suppression and inertia vibration device. The main contents are as follows:
According to the nonlinear characteristics of 1. large suspended vibration equipment key parts suspended elastic flexible suspender is studied. A flexible suspension rod axial force mechanical transverse nonlinear large deformation beam model. Considering the beam axial elongation, geometric nonlinear lead to large rotation and large deformation, and the force balance equation is set up on the basis of beam configuration large deformation, the large lateral deflection of beam nonlinear differential equations of axial force. Through numerical simulation, analyzed the influence of axial force, lateral force and deformation of the beams on the two ends of the beam boundary conditions; the free end of the flexible suspender transverse and axial curve of nonlinear elastic deformation, provide a theoretical basis for dynamics modeling of suspension vibration equipment.
2. proposed high Fang Ping sieve system dynamics modeling method of rigid flexible coupling analysis. The geometric constraints of four groups of suspender bundle deformation movement and body motion, a nonlinear dynamic model of inertial vibrating equipment, calculation method of steady-state amplitude and low natural frequency are given. Using the finite element method, response analysis the modal analysis and the dynamics of the system, and the screen body steady running state were tested. The experimental results verify the theoretical analysis.
3. for the high Fang Ping sieve resonance in the starting phase, the system self adjustable inertial exciting way of starting a multi field coupling transient process is studied. Considering the flexible suspender beam free end lateral stiffness nonlinear, transient process and rolling bearing friction starting asynchronous motor, established a system of starting transient process just. Soft power, multi field coupling mathematical model. Analyzed the transient resonance excitation mode of the original starting, development and decay process, self adjustable excitation mode to start transient resonance suppression mechanism was revealed. In depth analysis of the self adjustable exciter parameters on starting transient resonance effects based on a a new variable stiffness self adjustable inertia vibration, the vibration mode can not only further reduce the starting phase, maximum instantaneous amplitude, but also reduce the sensitivity of the damping effect on the relevant parameters, to improve the damping Robustness.
4. for the high Fang Ping sieve resonance in the stage of the parking, parking system transient self adjustable inertial exciter is studied by numerical simulation. Considering the characteristics of mechanical brake asynchronous motor, analyzes the produce mechanism of the excitation mode of parking transient resonance, revealing the self adjustable excitation and inhibition mechanism influence on the transient resonance factors. Research on parking system parking transient process of a novel vibration mode, a new excitation mode can also make the starting and stopping phase transient resonance obtain good suppression effect, provides a new method for suppressing transient inertial vibration mechanical resonance.
5. of high Fang Ping sieve dynamic strength and dynamic design method is studied. Using the finite element method for structural dynamic analysis, found the main reason of structure failure. Analysis of effect factors on the risk of stress, put forward various measures to improve the structural strength, these measures and methods in cooperation with engineering practice proved to be effective. Analysis of the high Fang Ping screen large-scale development, more conducive to maintain good dynamic strength. Through the structural design
Through the study of the key problems mentioned above, a set of modeling theories and dynamic design methods adapted to the large-scale and high reliability of high Fang Ping sieves have been formed in this paper.

【學(xué)位授予單位】：南京理工大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：TH237.6

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 熊萬里,何R，

本文編號：1389293