Results 221 to 230 of about 116,428 (235)

Recovering the functional form of the nonlinear roll damping of ships from a free-roll decay experiment: An inverse formulism

Ocean Engineering, 2010
Abstract The purpose of this paper is to identify the functional form of the nonlinear roll damping for a particular ship based on an experiment. The problem of damping identification is formulated as an integral equation of the first kind. However, the solution of the problem lacks stability properties, due to the ill-posedness of the first-kind ...
Jin Lee, Taek Soo Jang, Soon-Goo Kwon
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The Prediction of Contact Pressure–Induced Film Thickness Decay in Starved Lubricated Rolling Bearings

Tribology Transactions, 2010
Under starved conditions the thickness and distribution of the lubricant film in an elastohydrodynamically lubricated (EHL) contact is directly related to the distribution of lubricant on the track in the inlet to the contact. In starved lubricated rolling bearings this lubricant distribution is determined by many effects.
Pieter Martin Lugt, Cornelis H. Venner, M.T. van Zoelen   +2 more
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Particle bed charge decay behaviour under high tension roll separation

Minerals Engineering, 2005
A new theory of particle discharge in high tension roll (HTR) separation is presented. The discharge dynamics of an isolated charged particle resting on a conducting surface are studied first. The analysis is extended to particle discharge in a homogenous particle bed.
Ziemski, M, Holtham, P. N.
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Estimation of Nonlinear Roll Damping by Analytical Approximation of Experimental Free-Decay Amplitudes

Journal of Ocean University of China, 2019
Damping is critical for the roll motion response of a ship in waves. A common method for the assessment of damping in a ship’s rolling motion is to perform a free-decay experiment in calm water. In this paper, we propose an approach for estimating nonlinear damping that involves a linear exponential analytical approximation of the experimental roll ...
Meng Shao, Jinwei Sun
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Estimation of Nonlinear Ship Roll Damping from Free-Decay Data

Journal of Ship Research, 1985
A common method of assessing the damping present in ship rolling motion is to perform a free-decay experiment, in which, in the absence of waves, the ship is given an initial roll amplitude and then released. By processing the resulting decaying, oscillatory trace it is possible to estimate quantitatively the degree of damping, even when this is ...
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The use of decay rates to analyse the performance of railway track in rolling noise generation

Journal of Sound and Vibration, 2006
Through the development and testing of theoretical models for rolling noise in the past, it has been well demonstrated that the rate of decay of vibration along the rail is closely linked to the noise performance of the track, since it controls the effective radiating length of the rail.
Jones, C.J.C., Thompson, D.J., Diehl, R.J.   +2 more
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Roll Decay Model Test of a Post Panamax Container Ship: Experimental and Numerical Analysis

Volume 7: CFD and VIV, 2013
The slender shape of a modern ship hull, exhibits a roll motion that is — in contrast to heave and pitch motion — submitted to large amplitudes and weak damping. This effect explains the importance of determining the roll damping of a hull and denotes the difficulty to measure such a small dynamic property. For the joint research project
Piehl, Henry, el Moctar, Bettar Ould
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Bilge Keel Influence on the Free Decay of Roll Motion of a Three-Dimensional Hull

Volume 7: Ocean Space Utilization; Professor Emeritus J. Randolph Paulling Honoring Symposium on Ocean Technology, 2014
The prediction of roll motion of a ship with bilge keels is particularly difficult because of the nonlinear characteristics of the viscous damping. Flow separation and vortex shedding caused by bilge keels significantly affect the roll damping and the magnitude of the roll response. To predict free response of roll, the Slender-Ship Free-Surface Random
Ronald W. Yeung, Yichen Jiang
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Experimental and Numerical Analysis of the Roll Decay Motion for a Patrol Boat

2009
An experimental and numerical study of the free roll decay motion for a vessel of the Italian Navy is presented. Experimentally both sea trials and model scale tests have been carried out; numerical analysis has been performed by means of unsteady RANS simulations.
R Broglia B Bouscasse A Di Mascio, C Lugni, P Atsavapranee   +2 more
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Rolling Contact Fatigue Transformations in Aero Steels: The Effect of Temperature on Microstructural Decay

2020
Bearing components undergo failure as a result of rolling contact fatigue (RCF), a prevalent issue in a range of applications including aero engines. RCF can be triggered by microstructural changes at the subsurface including the formation of white etching areas (WEAs), dark etching regions (DERs), and white etching bands (WEBs).
Finn Sykes, X.Z. Liang, Pedro E.J. Rivera-Díaz-del-Castillo   +2 more
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