An Experimental Study on the Manoeuvrability of KCS with Different Scale Ratios by Free Running Model Test

This paper studies behavior of ship in head waves, when her bow dips under water, which leads to hydrodynamic forces and moments to be assessed. This paper presents model test data obtained in the test tank on the model of ship bow (hydrodynamic loads on forecastle deck during wave capture) as well as updates the coefficient of flow around the bow. The study also shows that bulwark has negative effect upon safety in these conditions because it significantly increases hydrodynamic loads on the deck.

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Experimental Study on the Influence of Appendages on a Yacht Rolling at Zero Froude Number

Marine Technology and SNAME News ◽

10.5957/mt1.2004.41.4.200 ◽

2004 ◽

Vol 41 (04) ◽

pp. 200-206

Author(s):

Kim Klaka ◽

Martin Renilson

Keyword(s):

Experimental Study ◽

Froude Number ◽

Model Test ◽

Roll Motion ◽

Forward Speed ◽

Test Results

Yachts tend to roll uncomfortably while at anchor, causing discomfort to the crew and passengers, generating additional stresses on equipment, and making such operations as embarking and disembarking hazardous activities. Currently, there is a dearth of data regarding roll motions at zero forward speed for hull shapes dominated by large appendages. Hence, an experimental study into the effect of large appendages on roll motion was undertaken. The model test results are presented, showing how changes in appendage geometry alter the roll response.

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Uncertainty Analysis of Free Running Manoeuvring Model Test on a Modern Ferry, With Emphasis on Heel Angles

Volume 7B: Ocean Engineering ◽

10.1115/omae2019-95513 ◽

2019 ◽

Author(s):

Anton Kisjes ◽

Frans Quadvlieg ◽

Victor Ferrari

Keyword(s):

Uncertainty Analysis ◽

Model Test ◽

Initial Conditions ◽

Test Series ◽

Confidence Bounds ◽

Approach Speed ◽

Twin Screw ◽

Free Running ◽

The Mean ◽

The Stability

Abstract This paper presents an uncertainty study on the manoeuvring behaviour of a twin screw ferry. In particular, we are interested in heel angles that this ship achieves while manoeuvring. Earlier published uncertainty analysis has focused on the uncertainty of overshoot angles and tactical diameters see [1] and [2]. The heel angles of these ships are not large. However, there is a class of ships that may encounter large heel angles due to steering. Ferries are such ships. The present paper quantifies also the uncertainty of the measured heel angles due to manoeuvres. During the model test series, results are obtained for various values of the stability (GM), where large heel angles are observed. This provides a unique insight in the relation between the GM, approach speed, directional stability and the achieved heel angles. Because of the demonstrated large heel angles, it was important to make an uncertainty analysis of these tests. More publications have been written on the uncertainty of overshoot angles and dimensions of turning circle manoeuvres. However, the uncertainty of heel angles during manoeuvres hasn’t been published yet, which makes this a unique paper. The uncertainty analysis will be based on repeat tests for the zigzag 10°/10° and 35° turning circle manoeuvres. Repeat tests are carried out for these manoeuvres to verify the mean and the uncertainty of the experimentally obtained values. The methodology for estimating the uncertainty with 95% confidence bounds are derived by accounting for 1) uncertainty from measurement, 2) repeat tests and 3) the uncertainty from propagation of initial conditions and the error in check angle and rudder. The uncertainty results are compared with a previous study of uncertainty of manoeuvring characteristics of model tests with the KVLCC2 [1] and [2].

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Experimental Study on Inner Reinforced Concrete-Block Composite Shaft Lining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.1316 ◽

2010 ◽

Vol 163-167 ◽

pp. 1316-1320

Author(s):

Hao Liang Jiang ◽

Ri Hui Liu

Keyword(s):

Experimental Study ◽

Reinforced Concrete ◽

Test Data ◽

Model Test ◽

Deformation Characteristic ◽

Concrete Block ◽

Vertical Shaft ◽

Composite Shaft ◽

Shaft Sinking ◽

Shaft Lining

Inner reinforced concrete-block composite shaft lining was widely used in vertical shaft sinking by vertical shaft sinking machine (VSM) and freezing shaft. In this paper, the deformation characteristic, failure Patten and the load Bering capacity of inner reinforced concrete-block composite shaft lining are presented ,based on the model test .and the test data are provide for the design and calculation of this kinds of composite shaft lining.

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Experimental study on different forms of fiber Bragg grating sensors detecting for rock model test

Transit Development in Rock Mechanics ◽

10.1201/b17617-4 ◽

2014 ◽

pp. 9-14 ◽

Cited By ~ 1

Author(s):

Q Yuan ◽

J Chai ◽

Y Li ◽

G Zhang

Keyword(s):

Experimental Study ◽

Fiber Bragg Grating ◽

Model Test ◽

Bragg Grating ◽

Fiber Bragg Grating Sensors ◽

Rock Model

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Experimental Study on Vortex-Induced Motions (VIM) of a Large-Volume Semi-Submersible Platform

Volume 7: CFD and VIV; Offshore Geotechnics ◽

10.1115/omae2011-49010 ◽

2011 ◽

Cited By ~ 4

Author(s):

Rodolfo T. Gonc¸alves ◽

Guilherme F. Rosetti ◽

Andre´ L. C. Fujarra ◽

Kazuo Nishimoto ◽

Allan C. Oliveira

Keyword(s):

Experimental Study ◽

Model Test ◽

Large Volume ◽

Cross Flow ◽

Induced Motion ◽

Line Cross

A great deal of work has been developed on the spar and monocolumn vortex-induced motion (VIM) issue. However, there are very few published works concerning VIM of semi-submersible platforms, partly due to the fact that VIM studies for this type of platform recently became interesting particularly due to the increasing semi-submersible dimensions (columns diameter and height. In this context, a meticulous experimental study on VIM for this type of platform concept is presented here. Model test experiments were performed to check the influence of many factors on VIM, such as different headings and hull appendages. The results comply with in-line, cross-flow and yaw motion amplitudes, as well as with combined motions in the XY plane.

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An Experimental Study on Progressive and Dynamic Damage Stability Scenarios

Volume 8A: Ocean Engineering ◽

10.1115/omae2014-23388 ◽

2014 ◽

Author(s):

Oliver Lorkowski ◽

Hendrik Dankowski ◽

Florian Kluwe

Keyword(s):

Experimental Study ◽

Model Test ◽

Static Model ◽

Model Tests ◽

Time Dependent ◽

Test Series ◽

Design Stage ◽

Damage Scenarios ◽

Damage Stability ◽

Set Up

Current damage stability rules for ships are based on the evaluation of a ship’s residual stability in the final flooding stage. The consideration of the dynamic propagation of water within the inner subdivision as well as intermediate flooding stages and their influence on the resulting stability is very limited in the current damage stability regulations. The investigation of accidents like the one of the Estonia or the European Gateway reveals that intermediate stages of flooding and the dynamic flooding sequence result in significant fluid shifting moments which have a major influence on the time-dependent stability of damaged ships. Consequently, the critical intermediate stages should be considered when evaluating designs with large cargo decks like RoRo vessels, RoPax vessels and car carriers. Also the safety of large passenger ships with respect to damage stability is affected by the aforementioned effects. In this context a new numerical flooding simulation tool has been developed which allows an evaluation of a ship’s time-dependent damage stability including all intermediate stages of flooding. The simulation model is based on a quasi-static approach in the time domain with a hydraulic model for the fluxes to ease the computation and allow for fast and efficient evaluation within the early design stage of the vessel. This allows studying multiple damage scenarios within a short period. For the further validation of this numerical simulation method a series of model tests has been particularly set up to analyse the time-dependent damage stability of a floating body. The test-body has been designed specifically to reflect the most typical internal subdivision layouts of ships affected by the effects mentioned above. The experimental study covers a static model test series as well a dynamic one. The static model test series has been set up with the aim to analyse the progressive flooding of selected compartments in calm water. Within the dynamic model test series, the model is excited by a roll motion oscillator to evaluate the influence of the ship motion on the water propagation and the associated damage stability. The model tests presented in this paper comprise side leaks in typical compartments which are used for a basic validation of the simulation toll and the measurement devices. Particular attention has been drawn on damage scenarios with critical intermediate flooding stages in consequence of restricted water propagation. The presented results enable a further validation of the numerical flooding simulation and give an insight view on the chosen experimental setup.

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Manoeuvrability of a Large Cruise Ship after Damage for Safe Return to Port

Journal of Marine Science and Engineering ◽

10.3390/jmse8050378 ◽

2020 ◽

Vol 8 (5) ◽

pp. 378

Author(s):

Tetsuhiro Yuura ◽

Hirotada Hashimoto ◽

Akihiko Matsuda

Keyword(s):

Simulation Model ◽

Model Test ◽

Model Experiment ◽

Cruise Ship ◽

Scaled Model ◽

Cruise Ships ◽

Head Waves ◽

Calm Water ◽

Free Running ◽

Captive Model Test

Free-running model tests were conducted using a scaled model of a large cruise ship with a damaged compartment, to investigate the effects of damage opening and floodwater on the manoeuvring performance in calm water and regular and irregular head waves. Drifting tests in regular beam waves were also performed. The experimental results indicated that the course-keeping ability in waves and turning ability became worse in the damaged condition. However, the target ship retained its manoeuvrability for safe return to the port, on its own, even in a damaged state. As it is time- and cost-consuming to conduct a free-running model experiment, a captive model test was also carried out to develop a system-based simulation model for evaluating the manoeuvrability of large cruise ships after damage.

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