本文關鍵詞： 波箔式箔片氣體軸承 端部泄露 平箔變形 承載力 姿態(tài)角 穩(wěn)定性　出處：《中國科學院研究生院（工程熱物理研究所）》2011年碩士論文　論文類型：學位論文

【摘要】：波箔式箔片氣體軸承被廣泛應用于各種高速透平機械,但承載力較低仍然是限制其應用的主要原因,為了提升箔片軸承的承載力,學者們不斷對箔片氣體軸承的結構進行優(yōu)化與改進。至今為止,波箔式箔片氣體軸承已經(jīng)發(fā)展到第四代,承載力也已經(jīng)得到較大提升。通過對箔片軸承的結構進行優(yōu)化從而提升承載力是在對箔片軸承靜態(tài)特性、動態(tài)特性的準確預測基礎上進行的。對箔片軸承靜態(tài)特性的分析離不開箔片軸承內(nèi)部氣膜的三維流場分析。 本文的研究工作就是在此基礎上展開的,主要內(nèi)容與結論如下： (1)建立了考慮平箔變形和氣體可壓縮性的耦合求解靜態(tài)特性的物理模型,利用有限差分法,通過Matlab自編程,完善了箔片軸承的靜態(tài)特性求解,模擬結果與NASA的實驗結果符合較好。并在此基礎上研究了箔片軸承參數(shù)對軸承承載力及穩(wěn)定性的影響。 (2)建立了具有壓力遠場邊界的三維網(wǎng)格模型,并用Fluent模擬了軸承內(nèi)部氣膜的三維流場,模擬結果與文獻結果符合很好。此外,得到了端部的流場分布、壓力分布以及泄露情況,與之前的文獻將端部壓力設定為環(huán)境壓力不一樣。在流場分析的基礎上,初步地分析了不同軸承參數(shù)下的流場,分析參數(shù)對承載力影響的內(nèi)部機理。 (3)分別建立了不考慮平箔變形和考慮平箔變形的靜態(tài)特性耦合求解的物理模型,并將結果進行對比,研究平箔變形對箔片軸承承載力和穩(wěn)定性的影響,結果顯示：平箔變形使得承載力降低,高轉速時穩(wěn)定性降低。通過用Fluent分別模擬了平箔不變形時和平箔變形時的三維流場,研究了平箔變形使承載力降低的流場內(nèi)部機理：平箔變形使得箔片軸承承載力下降的原因在于平箔變形形成的槽道使得軸承內(nèi)部的氣體的切向流阻增大,從而導致氣體切向運動減弱,整個端部的軸向運動增強,泄露增大,而不是因為平箔變形形成的槽道為氣體泄露提供了通道,也不是因為平箔變形使得氣膜厚度增大從而導致承載力降低。 (4)研究了平箔參數(shù)(厚度、彈性模量、泊松比)對平箔變形和軸承性能的影響；鑒于第二代波箔式箔片氣體軸承的結構形式,研究了端部波箔剛度對軸承性能的影響。此外,在對箔片軸承端部泄露分析的基礎上,研究了端部供氣壓力對箔片軸承性能的影響。 (5)在平箔參數(shù)、端部波箔剛度、端部供氣壓力分析的基礎上,對箔片軸承的平箔參數(shù)、端部波箔剛度、端部供氣壓力進行優(yōu)化,提升了承載力和穩(wěn)定性。
[Abstract]:Foil foil gas bearing is widely used in various high speed turbine machinery, but its low bearing capacity is still the main reason to limit its application, in order to enhance the bearing capacity of foil bearings, Scholars continue to optimize and improve the structure of foil gas bearings. So far, foil foil gas bearings have been developed to 4th generations, The bearing capacity has also been greatly improved. By optimizing the structure of foil bearings, the lifting capacity is based on the static characteristics of foil bearings. Based on the accurate prediction of the dynamic characteristics, the analysis of the static characteristics of foil bearing is inseparable from the three-dimensional flow field analysis of the inner film of foil bearing. The main contents and conclusions are as follows:. In this paper, a physical model considering the deformation of foil and the compressibility of gas is established to solve the static characteristics of foil bearings. The finite difference method is used to solve the static characteristics of foil bearings by Matlab self-programming. The simulation results are in good agreement with the experimental results of NASA, and the influence of foil bearing parameters on bearing bearing capacity and stability is studied. (2) A three-dimensional mesh model with a pressure far field boundary is established, and the three-dimensional flow field of the gas film inside the bearing is simulated by Fluent. The simulation results are in good agreement with the literature results. In addition, the distribution of the flow field, the pressure distribution and the leakage at the end of the bearing are obtained. On the basis of the flow field analysis, the flow field under different bearing parameters is preliminarily analyzed, and the internal mechanism of the influence of the parameters on the bearing capacity is analyzed. (3) physical models of coupling solution of static characteristics without and without foil deformation are established, and the effect of foil deformation on bearing capacity and stability is studied by comparing the results. The results show that the deformation of flat foil reduces the bearing capacity and the stability of flat foil at high speed. The three-dimensional flow field of flat foil without deformation is simulated by Fluent. The internal mechanism of the flow field in which the bearing capacity is reduced by the deformation of flat foil is studied. The reason that the bearing capacity of foil is reduced by the deformation of flat foil is that the groove formed by the deformation of flat foil increases the tangential flow resistance of the gas inside the bearing. As a result, the tangential movement of the gas weakens, the axial motion of the entire end increases, and the leakage increases, rather than because the groove formed by the deformation of the flat foil provides the passage for the gas leak. It is not due to the deformation of flat foil that the film thickness increases and the bearing capacity decreases. (4) the effects of foil parameters (thickness, modulus of elasticity, Poisson's ratio) on the deformation of flat foil and bearing performance are studied. In view of the structure form of the second generation foil foil gas bearing, the effect of end wave foil stiffness on bearing performance is studied. Based on the analysis of the tip leakage of foil bearing, the effect of end gas supply pressure on the performance of foil bearing is studied. 5) based on the analysis of foil parameters, end wave foil stiffness and end gas supply pressure, the foil parameters, end wave foil stiffness and end gas supply pressure of foil bearing are optimized, and the bearing capacity and stability are improved.
【學位授予單位】：中國科學院研究生院（工程熱物理研究所）
【學位級別】：碩士
【學位授予年份】：2011
【分類號】：TH133.3

【參考文獻】

相關期刊論文 前8條

1 鄧建,胡連桃,黃昌華,孔華;箔片空氣軸承的新近技術突破與應用進展[J];軸承;2004年08期

2 劉占生;許懷錦;;波箔型動壓氣體徑向軸承的應用與研究進展[J];軸承;2008年01期

3 許懷錦;劉占生;張廣輝;王永亮;;波箔片氣體動壓徑向軸承氣膜壓力分布特點[J];軸承;2008年06期

4 龔煥孫,張鴻興,周國明;徑向波箔軸承的設計計算和試驗研究——(Ⅰ)理論分析[J];上海機械學院學報;1991年04期

5 虞烈,戚社苗,耿海鵬;彈性箔片空氣動壓軸承的完全氣彈潤滑解[J];中國科學E輯:工程科學 材料科學;2005年07期

6 李二圣;陳國定;;動壓徑向波箔軸承靜態(tài)承載性能研究[J];機械設計與制造;2007年04期

7 侯予,熊聯(lián)友,王瑾,劉井龍,陳純正;箔片式動壓徑向氣體軸承的發(fā)展[J];潤滑與密封;2000年02期

8 戚社苗;耿海鵬;郭海剛;虞烈;;彈性箔片動壓氣體推力軸承承載性能研究[J];潤滑與密封;2006年05期

，

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