1998 Fiscal Year Final Research Report Summary
Tribo-Optimum Design of Fluid Bearings Considering Vibration and Its Experimental Verification
| Project/Area Number |
09650170
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
設計工学・機械要素・トライボロジー
|
|---|
| Research Institution | Tokai University |
|---|
Principal Investigator |
HASHIMOTO Hiromu Tokai University, School of Engineering, Prof., 工学部, 教授 (40130877)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Machine Element / Tribology / Optimum Design / Rotating Machine / Non-Circular Bearing / Journal Bearing / Stability / Oil Whirl |
|---|
| Research Abstract |
Hydrodynamic journal bearings have been widely used to support high-speed rotating machinery such as turbines, compressors and pumps. Especially, among of various types of hydrodynamic journal bearings, elliptical journal bearings are popular because of their simple structure, relatively low manufacturing costs and superior durability due to the high load carrying capacity and stability. Therefore, it is an important engineering problem to improve the performance characteristics of elliptical journal bearings in the high-speed operation conditions for enhancing the quality of rotating machinery. Generally, as the performance characteristics of high-speed elliptical journal bearings are governed by a number of bearing parameters, the bearing designers usually try to select the design variables by the conventional trial and error method using many design charts.
In this research work, the improvement of performance characteristics of high-speed hydrodynamic journal bearings by optimum des
… More
ign was developed and the results were compared with the experimental results. The conclusions are briefly summarized as follows :
(1) The general optimum design methodology combining the direct search method and SQP was developed for improving the static and dynamic characteristics of high-speed hydrodynamic journal bearings.
(2) The optimum design methodology developed was applied to the elliptical journal bearing design. The four design variables such as vertical and horizontal clearances, bearing length-to-diameter ratio and bearing orientation angle were determined effectively to minimize the weighted sum of oil film temperature rise, leakage oil flow rate and the inversion of whirl onset speed for a high-speed range of journal rotational speed.
(3) The optimized bearing characteristics were compared with the characteristics calculated from the random selected design variables, and then the effectiveness of optimum design was confirmed. Moreover, the effectiveness was also confirmed experimentally.
The optimum design methodology developed here can be easily applied to other types of high-speed hydrodynamic journal bearings such as three-lobe, offset, stepped tilting pad bearings etc. Less
|
