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A Review of the Prediction of Squat in Shallow Water

Published online by Cambridge University Press:  21 October 2009

A. Millward
A. Millward
Affiliation:
(University of Liverpool)
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Abstract

Recent evidence has shown that the effect of a ship moving in shallow water and the resultant squat are not well understood. This paper reviews the general problem of a ship in shallow water and illustrates the corresponding resistance, trim and sinkage at both sub-critical and also at super-critical speeds.

The paper then reviews the various methods of predicting the squat of a ship in shallow water in the sub-critical range, which is applicable to most ships. It is suggested that the simple rule-of-thumb methods are, at best, unreliable and the paper gives examples of empirical methods which have been tested against various sets of data and seem to give more representative answers. A summary of the notation used is given at the end of the paper.

Keywords

1. Hydrodynamics.2. Squat.3. Shallow water.4. Ship handling.

Information

Type
Research Article
Information
The Journal of Navigation , Volume 49 , Issue 1 , January 1996 , pp. 77 - 88
Copyright
Copyright © The Royal Institute of Navigation 1996

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