Unsteady finite-depth effects during resistance tests on a ship model in a towing tank

Alexander H. Day, David Clelland, Lawrence J. Doctors

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

This paper covers an extension of the study of Doctors et al. (J Ship Res 52(4):263-273, 2008) on oscillations in wave resistance during the constant-velocity phase of a towing-tank resistance test on a ship model to the case of relatively shallow water. We demonstrate here that the unsteady effects are very prominent and that it is essentially impossible to achieve a steady-state resistance curve in a towing tank of typical proportions for a water-depth-tomodel-length ratio of 0.25. This statement is particularly true in the speed region near a depth Froude number of unity. However, on the positive side, we show here that an application of unsteady linearized wave-resistance theory provides an excellent prediction of the measured total resistance, when one accounts for the form factor in the usual manner. Finally, a simple application of the results to the planning and analysis of towing-tank tests is presented.
LanguageEnglish
Pages387-397
Number of pages11
JournalJournal of Marine Science and Technology
Volume14
Issue number3
DOIs
Publication statusPublished - 1 Sep 2009

Fingerprint

Ship model tanks
Ship models
towing
Froude number
Phase velocity
phase velocity
Water
water depth
Ships
shallow water
oscillation
Planning
prediction
effect
ship
test

Keywords

  • unsteady wave resistance
  • towing tank
  • model tests
  • shallow water

Cite this

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Unsteady finite-depth effects during resistance tests on a ship model in a towing tank. / Day, Alexander H.; Clelland, David; Doctors, Lawrence J.

In: Journal of Marine Science and Technology, Vol. 14, No. 3, 01.09.2009, p. 387-397.

Research output: Contribution to journalArticle

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AU - Day, Alexander H.

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