氣靜壓軸承用補償式節流器之設計開發與特性探討

Development and Research of an Aerostatic Bearing with Self-Compensation Restrictor

施克明(Ke-ming Shih)

指導教授 ： 黃光裕

國立臺灣大學/工學院/機械工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01028

摘要

本論文之研究目的在於設計開發通用於氣靜壓軸承之補償式節流器，並通過理論分析與實驗測試特討其特性表現。補償式節流器會依據氣靜壓軸承內部壓力之變化進行流量的調節，使氣靜壓軸承夠擁有較大軸承剛性與穩定性。經過各式節流器型式評比比較，本論文選用簧片作為補償式節流器之主要作動元件，搭配各種節流毛細管之變化來達到流量補償弁遄C理論分析上，利用雷諾方程式與伯努力方程式推導出節流器中的壓力與流量變化方程式，同時以等效電路模擬節流器中動靜態弁鉒S性。氣體之可壓縮性所產生之氣鎚效應也可以利用Routh-Hurwitz準則所推導之穩定方程式進行推測。在細部改變設計中，也使用Ansys有限元素分析模組Flotran CFD進行設計參數對壓力變化之分析。實驗測試上，則針對數個開發節流器雛形進行作用力和剛性對氣膜間隙之探討，以確認各項設計與操作參數之影響。

關鍵字

補償式節流器 ； 氣靜壓軸承 ； 氣鎚現象 ； 節流器

並列摘要

Besides to design and develop the self-compensation restrictor, the aim of this paper is to find out its characteristic through the principle and the experimental result. As the pressure changes, the self-compensation restrictor adjusts the mass flow and thus increases the bearing’s stiffness and its stability. After comparing different types of restrictors, the spring plates was chosen to be the major active device of compensation restrictor; co-operated with different capillaries to optimize the flow change compensation. The pressure and mass flow equations in the restrictor can be find out from the theory of Reynolds’s equation and Bernoulli’s equation. Furthermore, by using the equivalent circuit, the static and dynamic characteristic can be simulated. Due to the compressibility of the air, the Routh-Hurwiz criterion is used to predict and avoid the pneumatic hammer phenomenon. In detail design, Flotran CFD, the finite element module developed by Ansys, is also used to analyze the effect of designing parameters to the pressure change. Finally, to validate its characteristic through various types of design and operating parameters, several restrictors are tested to find out the relationship between the effect force and the gap height.

並列關鍵字

restrictor ； pneumatic hammer ； aerostatic bearing ； self-compensation

參考文獻

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