Skip to main content

Research Repository

See what's under the surface

Study of gas/liquid behavior within an aeroengine bearing chamber

Wiedemann, Nikolas; Collicott, Steven H.; Chandra, Budi; Simmons, Kathy; Collicott, Steven; Pickering, Stephen; Wiedemann, Nicholas

Authors

Nikolas Wiedemann

Steven H. Collicott

Budi Chandra Budi.Chandra@uwe.ac.uk
Senior Lecturer in Aerospace Engineering

Kathy Simmons

Steven Collicott

Stephen Pickering

Nicholas Wiedemann



Abstract

Aeroengine bearing chambers typically contain bearings, seals, shafts and static parts. Oil is introduced for lubrication and cooling and this creates a two phase flow environment that may contain droplets, mist, film, ligaments, froth or foam and liquid pools. Some regions of the chamber contain a highly rotating air flow such that there are zones where the flow is gravity dominated and zones where it is rotation dominated. The University of Nottingham Technology Centre in Gas Turbine Transmission Systems, is conducting an ongoing experimental program investigating liquid and gas flow behavior in a relevant highly rotating environment. Previously reported work by the UTC has investigated film thickness and residence volume within a simplified chamber consisting of outer cylindrical chamber, inner rotating shaft and cuboid off-take geometry (termed the generic deep sump). Recently, a more aeroengine relevant bearing chamber offtake geometry has been studied. This geometry is similar to one investigated at Purdue University and consists of a "sub-sump" region approached by curved surfaces linked to the bearing chamber. The test chamber consists of an outer, stationary cylinder with an inner rotating shaft. The rig runs at ambient pressure and the working fluid (water) is introduced either via a film generator on the chamber wall or through holes in the shaft. In addition to visual data (high speed and normal video), liquid residence volume within the chamber and film thickness were the two numerical comparators chosen. Data was obtained for a number of liquid supply rates, scavenge ratios and shaft rotation speeds. The data from the current model is compared to that from the earlier studies. The data shows that in contrast to the previously reported generic deep sump study, the residence volume of the curved wall deep sump (CWDS) designs is far less sensitive to shaft speed, liquid supply rate and scavenge ratio. The method of liquid supply only makes a significant difference at the lowest scavenge ratios. Residence volume data for the Nottingham CWDS is comparable, when appropriately scaled, to that for the Purdue design. The film thickness data shows that at the lower shaft speeds investigated the flow is gravity dominated whereas at higher shaft speeds shear dominates. © 2013 by ASME.

Journal Article Type Article
Publication Date May 15, 2013
Journal Journal of Engineering for Gas Turbines and Power
Print ISSN 0742-4795
Electronic ISSN 1528-8919
Publisher American Society of Mechanical Engineers
Peer Reviewed Peer Reviewed
Volume 135
Issue 5
APA6 Citation Wiedemann, N., Collicott, S. H., Chandra, B., Simmons, K., Pickering, S., Collicott, S., & Wiedemann, N. (2013). Study of gas/liquid behavior within an aeroengine bearing chamber. Journal of Engineering for Gas Turbines and Power, 135(5), https://doi.org/10.1115/1.4007753
DOI https://doi.org/10.1115/1.4007753
Keywords scavenge, bearing chamber, gas turbine, multiphase flow
Publisher URL http://dx.doi.org/10.1115/1.4007753