静・動特性の飛躍的向上を目的としただ円ジャーナル軸受の最適設計

抄録

This paper describes the optimum design methodology for remarkable improvement of the static and dynamic characteristics of hydrodynamic journal bearings and its application to elliptical journal bearing design used in high-speed rotating machinery. The hybrid optimization technique combining the direct search method and the successive quadratic programming(SQP)is applied effectively to find the optimum solutions. In the optimum design of elliptical journal bearings, the four design variables such as vertical and horizontal bearing clearances, bearing lenght-to-diameter ratio and bearing orientation angle are determined to minimize the objective function defined by the weighted sum of oil film temperature rise, leakage flow rate and the inversion of whirl onset speed of the journal under many constraints. The results obtained are shown in graphical form for a wide range of journal rotational speed. Comparing the optimized static and dynamic characteristics with the characteristics calculated from the random selected design variables, the effectiveness of optimum design is verified.