本文選題：多機(jī)組軸系　切入點(diǎn)：有限單元法　出處：《東北大學(xué)》2012年碩士論文

【摘要】：我國空分裝備的生產(chǎn)從20世紀(jì)50年代的30m3/h小型設(shè)備到現(xiàn)在110000m3/h的超大型空分設(shè)備,正在朝特大型化發(fā)展。調(diào)研國內(nèi)空分裝備發(fā)展現(xiàn)狀發(fā)現(xiàn),國產(chǎn)大型空分機(jī)組運(yùn)行可靠性差,故障頻發(fā),連續(xù)運(yùn)行周期是國外設(shè)備的1/2-2/3,停機(jī)損失嚴(yán)重,重特大事故時有發(fā)生。因此,研究旋轉(zhuǎn)機(jī)械多機(jī)組軸系同步運(yùn)行穩(wěn)定性對空分裝備的穩(wěn)定、安全運(yùn)行有著非常重要的意義。 本文的研究對象為某大型壓縮機(jī),研究其低壓端由大齒輪、汽輪機(jī)、中壓缸轉(zhuǎn)子、低壓缸轉(zhuǎn)子組成的四跨軸系的同步運(yùn)行穩(wěn)定性。多機(jī)組軸系各機(jī)組在安裝前均進(jìn)行了單機(jī)動平衡,但組裝以后仍出現(xiàn)振動超標(biāo)的問題。本文對多跨軸系建立動力學(xué)模型,在ANSYS軟件環(huán)境下進(jìn)行模態(tài)、諧響應(yīng)分析,研究其運(yùn)行穩(wěn)定性,并進(jìn)一步運(yùn)用ANSYS軟件編程對多軸系系統(tǒng)的固有頻率和振動量進(jìn)行優(yōu)化,最后運(yùn)用MATLAB軟件計算了軸系系統(tǒng)的標(biāo)高,進(jìn)行了以下工作： (1)采用有限單元法對軸系系統(tǒng)進(jìn)行單元節(jié)點(diǎn)的劃分,運(yùn)用APDL語言在ANSYS軟件中建立了旋轉(zhuǎn)機(jī)械多機(jī)組軸系系統(tǒng)的動力學(xué)模型； (2)在建立好的模型基礎(chǔ)上,進(jìn)一步利用ANSYS軟件對旋轉(zhuǎn)機(jī)械多機(jī)組軸系這個轉(zhuǎn)子系統(tǒng)進(jìn)行動力學(xué)特性分析,包括了模態(tài)分析和諧響應(yīng)分析,其中模態(tài)分析分別考慮了彎曲振動和扭轉(zhuǎn)振動,求得系統(tǒng)前20階固有頻率、臨界轉(zhuǎn)速及振型,分析了系統(tǒng)在工作轉(zhuǎn)速下的運(yùn)行穩(wěn)定性；利用諧響應(yīng)分析分析了在工作轉(zhuǎn)速下,不平衡量對整個軸系系統(tǒng)的影響,其中汽輪機(jī)軸端的不平衡量對整個軸系影響最大； (3)在前面章節(jié)對該軸系建立的動力學(xué)模型、進(jìn)行動力學(xué)特性分析的基礎(chǔ)上,利用ANSYS軟件APDL語言編程對整個多機(jī)組軸系系統(tǒng)進(jìn)行了動態(tài)優(yōu)化設(shè)計,分別采用了零階方法和一階方法對轉(zhuǎn)子系統(tǒng)固有頻率及總振動量這兩個目標(biāo)進(jìn)行了優(yōu)化,并比較兩種優(yōu)化方法對不同優(yōu)化目標(biāo)的優(yōu)缺點(diǎn),且得到了較好的優(yōu)化結(jié)果； (4)考慮軸系中每根轉(zhuǎn)子在重力的作用下會彎曲,軸系標(biāo)高變化對軸承載荷分配產(chǎn)生影響,為了保證機(jī)組運(yùn)轉(zhuǎn)平穩(wěn),轉(zhuǎn)子相聯(lián)后轉(zhuǎn)動中心必須形成一條光滑的曲線(撓度曲線),各軸承所承受的載荷符合設(shè)計要求,本文采用MATMAB軟件編程計算確定各軸承標(biāo)高,得到了軸系撓度曲線和實(shí)際的支承反力,為今后的工作打下基礎(chǔ)。
[Abstract]:The production of air separation equipment in China is developing from the 30m3/h small equipment in the 1950s to the super large air separation equipment in 110000m3/h now. After investigating the present development situation of domestic air separation equipment, it is found that the operational reliability of domestic large air separation units is poor. The failure frequency and continuous operation period are 1 / 2 / 2 / 3 of the foreign equipment, the downtime loss is serious, and serious and serious accidents occur. Therefore, the study on the stability of the synchronous operation of multi-unit shafting of rotating machinery to the stability of the air separation equipment, Safe operation is of great significance. The research object of this paper is a large compressor. The low pressure end of the compressor is made up of big gear, steam turbine, medium pressure cylinder rotor. The stability of four span shafting system composed of low pressure cylinder rotors. The single machine dynamic balance is carried out for each unit of multi-unit shafting before installation, but the vibration exceeds the standard after assembling. The dynamic model of multi-span shafting is established in this paper. Modal and harmonic response analysis are carried out under the ANSYS software environment. The stability of the system is studied, and the natural frequency and vibration of the multi-shafting system are optimized by using ANSYS software. Finally, the elevation of the shafting system is calculated by using MATLAB software. The following were carried out:. 1) using the finite element method to divide the unit nodes of the shafting system, and using APDL language to establish the dynamic model of the shafting system in the ANSYS software. 2) on the basis of the established model, the dynamic characteristics of the rotor system of multi-unit rotor system of rotating machinery are analyzed by using ANSYS software, including modal analysis and harmonic response analysis. The modal analysis considers the bending vibration and the torsional vibration respectively, obtains the first 20 natural frequency, critical speed and mode shape of the system, analyzes the stability of the system under the working speed, and analyzes the operating speed under the working speed by using the harmonic response analysis. The influence of the unbalance on the whole shafting system, in which the unbalance at the shaft end of the steam turbine has the greatest influence on the whole shafting system; 3) based on the analysis of the dynamic characteristics of the shafting model established in the previous chapter, the dynamic optimization design of the whole shafting system of multi-unit is carried out by using the ANSYS software APDL programming language. The zero order method and the first order method are used to optimize the natural frequency and the total vibration of the rotor system, and the advantages and disadvantages of the two optimization methods for different optimization objectives are compared, and the better optimization results are obtained. (4) considering the bending of each rotor in the shafting under the action of gravity, the change of the elevation of the shafting has an effect on the load distribution of the bearing, in order to ensure the smooth operation of the unit, The rotation center of the rotor must form a smooth curve (deflection curve). The load of each bearing meets the design requirements. This paper uses MATMAB software to calculate and determine the elevation of each bearing. The deflection curve of shaft system and the actual supporting reaction force are obtained, which will lay the foundation for future work.
【學(xué)位授予單位】：東北大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：TH17

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 洪杰,韓繼斌,朱梓根;用整體傳遞系數(shù)法分析轉(zhuǎn)子系統(tǒng)動力特性[J];北京航空航天大學(xué)學(xué)報;2002年01期

2 沈華雄;朱均;;汽輪發(fā)電機(jī)組靜態(tài)標(biāo)高及靜態(tài)支反力的計算分析[J];東方電氣評論;1992年02期

3 高N，

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