Acoustic journal bearing—A search for adequate configuration

Abstract

Classical non-contact bearings are already used in a number of specialist applications. However, there are some specialist areas where they cannot be used for variety of reasons. The paper presents the search for an optimal configuration of an acoustic journal bearing and shows that the overall shape of the bearing and its geometry are of a vital importance for the load capacity of the bearing. The results presented and discussed in the paper clearly demonstrate that the acoustic journal bearing with appropriate geometry can develop a load capacity of magnitude that can be sufficient for some practical applications. Dear Editor-in Chief, I should be grateful for initiating the assessment procedure of our paper entitled 'Acoustic journal bearing -a search for adequate configuration'.Please let me know the outcome of the review in due time. The paper has not been published and is not under consideration for publication. 2The paper does not contain material which could create any issue of copy write or require permission for reproduction. *Statement of Originality Highlights (i)The paper demonstrates practical feasibility of an acoustic air bearing.(ii) It stresses the importance of the geometrical configuration of the bearing for the acoustic levitation effect.(iii) It contains experimental results showing the load capacity of the pressure generated by squeeze film acoustic levitation.(iv) Ranks three different geometries of the bearing in accordance with the magnitude of the torque required to initiate motion of the shat for a number of loads on the bearing. *Highlights (for review)Acoustic journal bearing -a search for adequate configuration R Gawarkiewicz, T A Stolarski 1) , K Tesch Gdansk University of Technology, Gdansk, Poland 1) also Brunel University London, United Kingdom e-mail: mesttas@brunel.ac.ukTel: +44 (0)1895266693 Abstract: Classical non-contact bearings are already used in a number of specialist applications. However, there are some specialist areas where they cannot be used for variety of reasons. The paper presents the search for an optimal configuration of an acoustic journal bearing and shows that the overall shape of the bearing and its geometry are of a vital importance for the load capacity of the bearing. The results presented and discussed in the paper clearly demonstrate that the acoustic journal bearing with appropriate geometry can develop a load capacity of magnitude that can be sufficient for some practical applications.

Acoustic journal bearing – Performance under various load and speed conditions

“…Taking into account results of experimental testing the dynamic performance of three bearings with different geometries can be ranked as follows: (i) G3 bearing, (ii) G2 bearing, and (iii) G1 bearing. Incidentally, this ranking is similar to that presented and discussed in the earlier paper dealing with the start-stop performance of these three bearings [23]. The current ranking is based on the magnitude of shaft's motion within the very lightly load bearing as expressed quantitatively by coefficients R1 and R2.…”

“…The search for the most effective geometry of the acoustic journal bearing and its outcomes are presented elsewhere [23]. As a result of that three configurations of the acoustic journal bearing were identified and selected for further experimental testing to determine they performance under various load and speed conditions.…”

“…Figure 1 shows the geometry and main dimensions of the first bearing (called G1). This particular geometry was arrived at on the basis of studies presented in [23]. The radial clearance used was 20 µm.…”

“…In principle, acoustic bearing should have most of the advantages of aerostatic bearings but external pressurized air supply is not needed and the bearing interface can be as simple as two plain surfaces; although design consideration is needed to create high frequency vibration of the bearing surfaces. From experiments [23] it is evident that acoustic pressure was sufficient to support a bearing spindle system even at its stationary state during the start and stop operation under a load. This system was tested experimentally for various geometry configurations of the bearing shell to determine its static load supporting capacity [23].…”

“…From experiments [23] it is evident that acoustic pressure was sufficient to support a bearing spindle system even at its stationary state during the start and stop operation under a load. This system was tested experimentally for various geometry configurations of the bearing shell to determine its static load supporting capacity [23]. It was found that the static load capacity of the bearing depends, to a large extent, on the geometry of the bearing shell.…”