Optimized Alignment of a USCG Polar Class Icebreaker Wing Shaft Using a Distributed Bearing Finite-Element Model

Abstract

There are indications that new analytical techniques must be employed for determining and optimizing the shaft alignment of the wing shafts of the U.S. Coast Guard's Polar Class icebreakers. These indications include failing shaft coupling bolts and excessive stress concentration factors in the shaft. Current design practices dictate the use of point bearing loads for both design and realignment analysis of propulsion shafts. In this work, a general purpose finite-element code is utilized for modeling the shaft. The bearings are modeled as flexible distributed supports. A public domain optimization routine is coupled to the analysis for determining the optimum shaft alignment. The new process is validated, and then utilized for analyzing the USCG Polar Class ice-breaker wing shafts. Results are presented and discussed.