【摘要】：本文首先采用多重網(wǎng)格法和多重網(wǎng)格積分法對等溫粗糙表面沖擊彈流問題進行了數(shù)值模擬分析。研究了表面粗糙波紋波長對等溫重力落球問題的影響。研究中還分析了鋼球初始下落高度、初始油膜厚度和鋼球質(zhì)量對沖擊油膜壓力和膜厚的影響。研究發(fā)現(xiàn)，沖擊高度的增加、初始油膜厚度的增加和鋼球質(zhì)量的增加均會使中心壓力第一壓力峰增大；中心膜厚隨沖擊質(zhì)量的增加和初始油膜厚度的增加而增大，而最小膜厚隨沖擊高度的增加而增大，隨初始油膜厚度的增加基本保持不變。隨著波長的增大，，每一瞬時的振幅下降也會增大。初始潤滑油膜厚度較小時振幅下降反而較大。 其次，在等溫落球問題的基礎(chǔ)上，運用多重網(wǎng)格法和多重網(wǎng)格積分法以及溫度逐列掃描法對粗糙表面沖擊熱彈流問題進行了分析。首先對表面余弦波紋對考慮熱效應的重力落球問題進行分析。接著將熱解與對應的等溫解比較，隨后分別研究了沖擊高度和初始油膜厚度對沖擊熱彈流問題的影響。研究發(fā)現(xiàn)，表面粗糙波紋使壓力、膜厚及油膜中層溫度發(fā)生劇烈波動。最高溫升和中心溫升隨著沖擊高度的增加均增大。隨著初始油膜厚度的增加，第一溫升峰和中心溫升均減小。 最后，采用數(shù)值分析方法研究沖擊載荷作用下偏心輪-挺桿副的微熱彈性流體動力潤滑問題。分析中假設(shè)平面挺桿表面分布有余弦波紋，探討了偏心距和余弦波波長對潤滑油膜變化的影響。數(shù)值模擬計算結(jié)果表明，在偏心輪-挺桿副工作的一個周期里，表面波紋度的存在會導致油膜壓力和溫度上升。在不同的滑滾比條件下，表面波紋的彈性變形程度不同。在兩表面反向運動的半個周期內(nèi)，隨偏心距的增加，滑滾比也增加，導致表面波紋的變形程度降低。
[Abstract]:In this paper, the impact elastohydrodynamic problem of isothermal rough surface is numerically simulated by multi-grid method and multi-grid integration method. The influence of surface rough ripple wavelength on isothermal gravity drop was studied. The effects of the initial falling height of the ball, the initial oil film thickness and the ball quality on the impact oil film pressure and film thickness are also analyzed. It is found that the increase of impact height, the increase of initial oil film thickness and the increase of ball mass will increase the first pressure peak of the center pressure. The central film thickness increases with the increase of the impact mass and the initial oil film thickness, while the minimum film thickness increases with the increase of the impact height, and remains basically unchanged with the increase of the initial oil film thickness. As the wavelength increases, the amplitude decreases with each instant. The amplitude of the initial lubricating oil film decreases greatly when the film thickness is small. Secondly, based on the isothermal drop problem, the impact thermal elastohydrodynamic problem of rough surface is analyzed by using multi-grid method, multi-grid integration method and temperature sequential scanning method. Firstly, the gravity ball drop problem considering the thermal effect is analyzed for the surface cosine ripple. Then, the effects of impact height and initial oil film thickness on the impact thermal elastohydrodynamic problem are studied by comparing the pyrolysis with the corresponding isothermal solution. It is found that the surface roughness ripples make the pressure, film thickness and oil film temperature fluctuate sharply. The maximum temperature rise and the center temperature rise increase with the increase of impact height. With the increase of the initial oil film thickness, the first temperature rise peak and the center temperature rise decrease. Finally, the micro-thermoelastic hydrodynamic lubrication of eccentric wheel-tappet pair under impact load is studied by numerical analysis method. The influence of eccentricity and cosine wave length on the variation of lubricating oil film is discussed. The numerical simulation results show that the existence of surface ripple will lead to the increase of oil film pressure and temperature during a period of work between eccentric wheel and tappet pair. The elastic deformation degree of surface ripple is different under different sliding ratio. With the increase of eccentricity, the slip / roll ratio increases during the half period of the reverse motion of two surfaces, which results in the decrease of the deformation degree of the surface ripple.
【學位授予單位】：青島理工大學
【學位級別】：碩士
【學位授予年份】：2012
【分類號】：TH117.2

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