Stephens, L. Scott*

Bearing and Seals Laboratory, Mechanical Engineering Dept., University of Kentucky
Computational Research Project on the DLX Cluster as of 8/5/2013

Lip Seal Performance Simulation

Description: The project aims to further develop a Fortran code previously developed by graduate students at UK. The code predicts performance and detailed physics of elastomer lip seals for rotating shafts. This is a fluid-structure interaction problem featuring an oil film about 1-2 um thick between shaft and seal. The sealing zone is about 300 um wide in the axial dimension. The film is subject to cavitation in low-pressure regions as dissolved gases come out of solution. The main difficulties are proper modeling of the physics and achieving convergence of the fluid-structure coupling iterations in a practical time. The coupling procedure is a fixed-point iteration: starting with a film thickness distribution, a new pressure field and the resulting film thickness are computed. The code iterates until the difference between successive estimates of film thickness distribution is small enough. Within each coupling iteration the code solves for the pressure field in the oil film with an ADI scheme. The deformation of the elastomer seal surface is computed by use of influence coefficients that describe the deformation field due to a point load in the radial or circumferential direction. Deformations due to point loads throughout the 2-D domain are summed. The project treats both steady state and time-dependent cases. The code is typically run on the DLX cluster on a single node with 16 threads.

Collaborators

Sponsor: Dr. Scott Lattime, Timken Bearing Co.
Principal Investigator: Prof. L. Scott Stephens (Chair, ME Dept.)
Project Personnel: Prof. Jonathan Wenk (ME Faculty)
Dr. David Weatherly (Research Staff)

Software:

The main code has been developed in this and previous projects at the Bearing and Seals Lab. Auxiliary programs include Matlab and MSC Marc; these are typically run offline. Using ANSYS

Grants:

Stephens, L. Scott 1004292 ThermoFluidic Modeling General Electric Appliances 1/31/2014 - 1/30/2015 $131,666

Publications:

“Experimental Benchmarking of Surface Textured Lip Seal Models, Ph.D. dissertation. Dr. Wei Li, University of Kentucky, 2012.
“Experimental Benchmarking of the Numerical Model of a Radial Lip Seal with a Surface Textured Shaft”, Wei Li, Lyndon S. Stephens, Jonathan Wenk; Tribology Transactions, 56: 75-87, 2013.
“Model Development And Investigation Of Micro-Deterministic Asperity Features/Textures Using The Jakobsson-Floberg-Olsson (JFO) Cavitation Condition Modified Reynolds Equation”, Masters’ Thesis, Daniel Impellizzeri, University Of Kentucky, 2006