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http://dx.doi.org/10.5762/KAIS.2017.18.12.135

A Study on Flexibility Acquisition Method for VLCC Shaft System  

Shin, Sang-Hoon (Department of Aero Mechanical Engineering, Kyungwoon University)
Ko, Dae-Eun (Department of Naval Architecture and Ocean Engineering, Dong-Eui University)
Publication Information
Journal of the Korea Academia-Industrial cooperation Society / v.18, no.12, 2017 , pp. 135-139 More about this Journal
Abstract
The main reason for heat accidents occurring at the after stern tube bearing (STB) is excessive local pressure caused by the deflection of the propulsion shaft due to propeller loads. The probability of a heat accident is increased by the low flexibility of the shaft system in very large crude oil carriers (VLCCs) as the engine power and shaft diameter increase and the distance decreases between the forward and after STBs. This study proposed shaft system with only an after STB and no forward STB for a flexibility acquisition method for a VLCC shaft system under hull deformation. A Hertzian contact condition was applied, which assumes a half-elliptical pressure distribution along the contact width for the calculation of the local squeeze pressure. The propeller loads, heat effect, and hull deflection under engine operating conditions are also considered. The results show that the required design criteria were satisfied by building a partial slope at the white metal, which is the material at the axial contact side in the after STB. This system could reduce building cost by simplification of the shaft system.
Keywords
Heat accident; Hertzian contact condition; Partial slope; Shaft system; Stern tube bearing;
Citations & Related Records
Times Cited By KSCI : 6  (Citation Analysis)
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