1. Analysis Of A Full Journal Bearing and the Effect of Wear on Performance
By: Marc Desjardins

2. Proposal
Detailing the theoretical analysis of a full journal bearing will be performed and compared to the results obtained by a computational fluid dynamic (CFD) analysis.
Wear, it’s potential causes, and prevention will be described and complemented by a CFD analysis of the effect of wear severity and location on the bearing performance and fluid characteristics.
The analysis will suggest possible system changes to correct problems resulting from wear.

3. What Bearing Wear Looks Like

4. How this analysis will be done
1. An in-depth explanation of lubrication and bearing theory and the derivation of the some of the classical equations used in bearing analysis.
2. A mathematical/theoretical analysis of a typical journal bearing with known inputs (rotational speed, length, clearance, etc.).
3. The same journal bearing analyzed above will be modeled and evaluated in COMSOL using a 2-dimensional fluid analysis. The results of the COMSOL analysis will be then be compared to the theoretical analysis.
4. The severity of wear will be varied to investigate the relationship between material loss and load capacity, pressure, and fluid velocity.
5. The radial location of a constant wear area will be varied along critical portions of the bearing to analyze the effect of wear location.

5. COMSOL Models Fluid pressure in typical journal bearing
Wear Site
Fluid pressure in typical journal bearing
Example of Modeling Wear

6. Analysis Will Include:
Wear Depth Vs Load Capacity, Maximum Pressure and Velocity
Wear Location Vs Load Capacity, Maximum Pressure, and Velocity
Potential system changes to reverse or negate the impact of bearing wear will be analyzed and suggested