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http://dx.doi.org/10.9725/kts.2021.37.4.117

The Effects of Inclined Foil Shape on Flow Characteristics in Air Foil Thrust Bearing Using CFD  

Baek, GeonWoong (Graduate School, Dept. of Mechanical Engineering, Yonsei University)
Joo, Won-Gu (Dept. of Mechanical Engineering, Yonsei University)
Mun, Hyeong Wook (Hanwha Power Systems)
Hwang, Sunghyen (Hanwha Power Systems)
Jeong, Sung-Yun (Hanwha Power Systems)
Park, Jung-Koo (Hanwha Power Systems)
Publication Information
Tribology and Lubricants / v.37, no.4, 2021 , pp. 117-124 More about this Journal
Abstract
In this study, we perform a 3D CFD conjugate analysis according to the shape of the foil ramp of the air foil thrust bearing, analyze the flow characteristics inside the bearing, and compare the results corresponding to the two shapes. Air has a lower viscosity than lubricating oil. Therefore, the thrust runner of the bearing must rotate at high speed to support the load. The gap between thrust runner and foil is significantly smaller than that of the oil bearing. Hence, it is crucial to analyze the complex flow characteristics inside the bearing to predict the complex flow inside the bearing and performance of the bearing. In addition, flow characteristics may appear differently depending on the ramp shape of the bearing foil, which may affect bearing performance. In this study, we numerically analyze the main flow path of air flowing into the bearing and the secondary flow path used for cooling the bearing using the commercial CFD software ANSYS CFX and compare the flow characteristics for straight and curved foil ramp shapes. Notably, there is a difference in the speed of the flowing air according to the shape of the ramp, which affects the bearing performance.
Keywords
air foil thrust bearing; computational fluid dynamics; hydrodynamic lubrication; load capacity; leakage rate;
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