Investigation of passive bearing for biomedical applications
Tham, Denise Wai Xi
Date of Issue2017
School of Mechanical and Aerospace Engineering
The Muijderman Equation was the basis for geometry modifications in this project. This was aimed at achieving positive pressure generation between the rotating spiral groove bearing and the stationary housing for hydrodynamic lift with varying geometrical parameters when the axial clearance gap between the two is 0.2mm. Previous investigations were conducted on a wide array of bearings and the I14O1420L spiral groove bearing was selected for this project to study the correlation between an increasing groove height at the outer radius and the pressure distribution within the spiral groove bearings. This series of tests were done with the aid of Computational Fluid Dynamics (CFD) whereby accurate and reliable results were presented and conclusions on the effects of a varying groove height were made. In the light of the Modified Muijderman Equation, the consistency of the results in this study emphasized on the impact of the inertia effects whereby higher rotational speeds resulted in higher negative differential pressure in the bearings. The determinant to a conclusion was to allow the optimal bearing to be simulated at an ideal rotational speed at various fluid film thicknesses such that comparisons against the original I14O1420L could be made. The results have proven that the I14O1420L bearing remains the best among its family of modified bearings.
Final Year Project (FYP)
Nanyang Technological University