Behaviour of porous aerostatic bearings with various restrictor permeabilities
Loading...
Access rights
openAccess
publishedVersion
URL
Journal Title
Journal ISSN
Volume Title
A4 Artikkeli konferenssijulkaisussa
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Date
Major/Subject
Mcode
Degree programme
Language
en
Pages
4
115-118
115-118
Series
Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021
Abstract
Aerostatic bearings are externally pressurized gas lubricated bearings. Aerostatic bearings are used in high speed and precision motion applications due to low friction and high accuracy. They use a restrictor to limit the flow of the gas into the bearing gap. The presence of the restrictor increases the stability of the bearing against self-excited vibrations. This study focuses on porous graphite restrictors and the effect of permeability on the behaviour of the bearing. The bearings were studied both experimentally and with a simulation model. Flat bearing pads with 37 mm diameter and different restrictor bulk permeability were manufactured and tested. Experimental measurements were conducted on a test setup allowing loading of the bearing against a ground steel plate. The load was supplied with a series of weights. The air gap was measured with a linear length gauge, measuring the displacement of the air bearing. The pressure was controlled with a regulator and the flow rate into the bearing was measured.In order to build an accurate simulation model, the permeability of the used material was calculated from the measured short circuit flow through each 4.5 mm thick sample. The flow in the porous material and in the restrictive layer follows Darcy’s law, the flow in the air gap is described by the Navier-Stokes-equation. The simulation model was validated with experimental results. Measurement and simulation results include the air gap height, load and flow rate at a supply pressure of 0.4 MPa. According to previous research and preliminary results the surface restrictor layer has increased the resistance of the bearing to self-excited air-hammer vibration, leading to a higher load capacity.Description
Publisher Copyright: © 2021 Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021. All rights reserved.
Other note
Citation
Hübner , M , Miettinen , M , Vainio , V , Cierpka , C , Theska , R & Viitala , R 2021 , Behaviour of porous aerostatic bearings with various restrictor permeabilities . in R K Leach , C Nisbet & D Phillips (eds) , Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021 . Proceedings of the 21st International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2021 , euspen , pp. 115-118 , International Conference of the European Society for Precision Engineering and Nanotechnology , Virtual, Online , 07/06/2021 .