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Title: A hydraulic absorber for wideband vibration reduction in ship hulls

Abstract

A vibration reduction of ship hulls by an active absorber system is proposed. In the scheme, a tuned mass is moved according to the hull vibration as measured by a multi-mode sensing system in order to generate a suitable active force for vibration reduction of hull girder. In order to supply the large amount of required power, a hydraulic servo system is implemented. Then the dynamic characteristic of the hydraulic system is considered for system design. Based on stochastic theory and optimal theory, the control law of the system is derived in order to approach the optimal level of vibration reduction. A 10-t absorber is applied to a 87,000-t oil tanker to demonstrate the feasibility of this scheme. The results show that the multi-peak values of resonance are suppressed in frequency response. Moreover, the vibration excited by propeller and engine is reduced to an extremely efficient level by this scheme.

Authors:
;  [1]
  1. (National Taiwan Univ., Taipei (Taiwan, Province of China). Dept. of Naval Architecture and Ocean Engineering)
Publication Date:
OSTI Identifier:
5085915
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Offshore Mechanics and Arctic Engineering; (United States); Journal Volume: 116:1
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; MECHANICAL VIBRATIONS; DAMPING; SHIPS; DYNAMIC LOADS; HYDRAULIC EQUIPMENT; EQUIPMENT; 423000* - Engineering- Marine Engineering- (1980-)

Citation Formats

Hsueh, W.J., and Lee, Y.J. A hydraulic absorber for wideband vibration reduction in ship hulls. United States: N. p., 1994. Web. doi:10.1115/1.2920127.
Hsueh, W.J., & Lee, Y.J. A hydraulic absorber for wideband vibration reduction in ship hulls. United States. doi:10.1115/1.2920127.
Hsueh, W.J., and Lee, Y.J. Tue . "A hydraulic absorber for wideband vibration reduction in ship hulls". United States. doi:10.1115/1.2920127.
@article{osti_5085915,
title = {A hydraulic absorber for wideband vibration reduction in ship hulls},
author = {Hsueh, W.J. and Lee, Y.J.},
abstractNote = {A vibration reduction of ship hulls by an active absorber system is proposed. In the scheme, a tuned mass is moved according to the hull vibration as measured by a multi-mode sensing system in order to generate a suitable active force for vibration reduction of hull girder. In order to supply the large amount of required power, a hydraulic servo system is implemented. Then the dynamic characteristic of the hydraulic system is considered for system design. Based on stochastic theory and optimal theory, the control law of the system is derived in order to approach the optimal level of vibration reduction. A 10-t absorber is applied to a 87,000-t oil tanker to demonstrate the feasibility of this scheme. The results show that the multi-peak values of resonance are suppressed in frequency response. Moreover, the vibration excited by propeller and engine is reduced to an extremely efficient level by this scheme.},
doi = {10.1115/1.2920127},
journal = {Journal of Offshore Mechanics and Arctic Engineering; (United States)},
number = ,
volume = 116:1,
place = {United States},
year = {Tue Feb 01 00:00:00 EST 1994},
month = {Tue Feb 01 00:00:00 EST 1994}
}
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