Structure design and simulation of frictionless cylinder-piston based on Fluent

SUN Jian-hui1， NI Xu-guang1， YUAN Qiao-ling1， SHAN Xiao-hang1， ZHOU Hai-qing2
（1. School of Mechanical Engineering， Zhejiang University of Technology， Hangzhou 310014， China；
2. Hangzhou Yuce Co. Ltd.， Hangzhou 310014， China）

Abstract： Aiming at the low radial bearing capacity，high gas consumption and working instability of the current cylinder-piston，combining with the ideas of air bearing，a more innovative frictionless cylinder-piston was presented. Based on the CFD software Fluent，the frictionless cylinder-piston fluid modal was established and the distribution of pressure along the axial direction of the piston was obtained. And comparing the method of traditional theory calculation and Fluent simulation，the relationship between eccentricity and radial bearing capacity was acquired. It is proved that the result of the traditional theory calculation and Fluent simulation is basically the same. And the latter's calculation result of the bearing capacity is less than 3.2% when eccentricity is in the range of 0.1 to 0.3. The smaller the eccentricity is，the smaller the error of simulation is. The results indicate that the design of cylinder-piston based on Fluent is validity and reliable.
Key words： air bearing； frictionless cylinder-piston； Fluent