整合套杯式氣靜壓軸承之氣渦輪轉子系統之設計開發與性能探討

Design and Development of an Integrated System with Cap-shaped Aerostatic Bearing and Air-Turbine Rotor and Research on Its Performance

吳翰杰(Han-Chieh Wu)

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(2010年)

https://doi.org/10.6342/NTU.2010.00348

摘要

氣靜壓軸承靠著低摩擦、自我降溫、零污染之特性被大量應用於高精度之導引、高速主軸以及半導體相關設備。然而由於氣體之可壓縮性，氣壓軸承普遍存在承載力較低、運作環境條件設限較嚴苛等缺陷。本論文提出一種新的套杯式氣靜壓軸承設計概念，藉由軸徑向氣膜互相連結成套杯形狀，藉此提升氣靜壓軸承之承載能力。兩個對置套杯式氣靜壓軸承整合一個氣渦輪轉子實體開發出一個高速轉子系統。運用理論計算和CFD軟體模擬，對氣靜壓軸承的設計參數對承載力與剛性影響進行分析探討，並利用田口法找出設計參數之最佳尺寸組合。透過各種實驗測試，驗證套杯式氣靜壓軸承的設計概念確實可以提升軸向與徑向承載能力，同時低摩擦的氣靜壓軸承也促進和提升氣渦輪轉子之轉動特性。依據實驗測試結果，套杯式氣靜壓軸承具有徑向承載力可達27.5 N，軸向承載力可達62 N，氣渦輪轉子也可達最大轉速為52 krpm。

關鍵字

氣靜壓軸承 ； 套杯式 ； 氣渦輪轉子 ； 承載力 ； 轉速 ； 田口法

並列摘要

Aerostatic bearings are widely applied in high-precision guiding systems, high-speed spindles and semiconductor correlated systems because of their low friction, self-cooling and no pollution characteristics. Due to the air compressibility, aerostatic bearings always possess inherent weaknesses such as lower bearing capacity and strict operational bounds. In this Thesis, we have proposed a novel design concept of capped aerostatic bearing, which combines the radial and the axial bearings inside a cap-shaped air film to enhance its bearing capacity. Two opposite working cap-shaped aerostatic bearings are integrated with an air-turbine rotor to set up a high-speed rotor system. By using theoretical analyses and computational fluid dynamics simulation, the influences of the design parameters of the cap-shaped aerostatic bearing on its bearing capacity and stiffness are analyzed. And through the Taguchi method, an optimal combination of design parameters is built up. Through diverse experimental tests on the integrated system, it can be verified that the design concept of the cap-shaped bearing can increase the radial and axial bearing capacity and stiffness; moreover, low-friction bearing can also facilitate and enhance the rotation of the air-turbine rotor. According to the testing results, the cap-shaped aerostatic bearing has the radial bearing capacity of 27.5 N and the axial bearing capacity of 62 N, and the air-turbine rotor also reaches the maximum rotational speed of 52 krpm.

並列關鍵字

Aerostatic bearing ； cap-shaped ； air-turbine rotor ； bearing capacity ； rotational speed ； Taguchi method

參考文獻

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