[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.9725/kts.2018.34.1.16

Performance Improvement of Cylindrical Turbine Guide Bearings with Pad Leading-Edge Tapers for Vertical Hydro-Power Application: Effects of Taper Angle and Length

Lee, An Sung (Dept. of System Dynamics Research, Korea Institute of Machinery and Materials (KIMM))
Jang, Sun-Yong (R&D Center, Daedong Metal Industry Co., Ltd. (DMB))
Park, Soo Man (Creative Future Laboratory, Korea Electric Power Research Institute (KEPRI))

Publication Information

Tribology and Lubricants / v.34, no.1, 2018 , pp. 16-22 More about this Journal

Abstract

Cylindrical turbine guide bearings (TGBs) with simple plain pads have conventionally been used in vertical hydro-power turbine-generator applications in order to provide turbine runner shafts with smooth rotation guides and supports. To overcome low-load/low-eccentricity performance drawbacks, such as very low film stiffness and lack of design credibility in the stiffness values themselves, of conventional cylindrical TGBs, the introduction of a rotational-directional leading-edge taper to each partitioned pad, simply pad leading-edge taper, has been found to be very effective in enhancing their design-application availability and usefulness. In this study, we investigate the effects of taper angle and length for given taper heights in detail in order to systematically establish the effectiveness of design on the performance improvement of vertical hydro-power application cylindrical TGBs with pad leading-edge tapers. The analysis results with $4-Pad{\times}1-Row$ cylindrical TGBs show that the lubrication performance of the cylindrical TGBs is optimized with an approximate taper angle ratio of 0.8 and taper length ratio of 0.9. We conclude that the introduction of pad leading-edge tapers along with the optimization of taper designs can be very effective in improving the overall operation reliability of cylindrical TGBs and the rotordynamic characteristics of vertical hydro-power turbine-generator rotor-bearing systems as well, to which the TGBs are applied.

Keywords

cylindrical turbine guide bearing; pad leading-edge taper; taper angle; taper length; performance improvement;

Citations & Related Records

Times Cited By KSCI : 1 (Citation Analysis)

Reference
Cited By KSCI

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