Design of retrofit devices using CFD, validated with wind tunnel tests


James, Marion C., Turnock, Stephen R. and Hudson, Dominic A. (2012) Design of retrofit devices using CFD, validated with wind tunnel tests. In, NuTTS 2012: 15th Numerical Towing Tank Symposium, Cortona, IT, 07 - 09 Oct 2012. 6pp.

Download

[img]
Preview
PDF
Download (2206Kb)

Description/Abstract

The energy efficiency design index (EEDI) currently under development will lead to high emission ships being taxed heavily in the future. As a result, many possible design solutions to increase the efficiency of high powered ships are currently being investigated. However, existing ships must rely on engine room systems upgrade or the use of retro-fit devices.

The aim was to seek a low cost approach to solve the challenge of how to improve the energy efficiency of existing ships. To demonstrate this approach a specific oil tanker hull form was studied and future novel methods of achieving a gain in propulsive efficiency were considered.

Wind tunnel and towing tank testing are used, in conjunction with opensource computational fluid dynamics modelling, to analyse the wake field changes caused by the devices. Changes in efficiency are assessed using the propeller efficiency modelled with a blade element momentum code. A testing procedure, explained in terms of methodology with objective justification for improvements has been developed. This procedure successfully detects changes in propeller efficiency at model scale due to devices, and thus provides a route to evaluate a wide variety of devices.

Preliminary results suggest that gains in efficiency of at least 3% could be obtained with simple vanes and 2% for pre-swirl ducts. These values could be greatly increased through further optimisation of device size, geometry, position and angle of attack.

Item Type: Conference or Workshop Item (Paper)
Keywords: CFD, ship wake, propeller efficiency, wind tunnel, blade element momentum
Subjects: V Naval Science > V Naval Science (General)
V Naval Science > VM Naval architecture. Shipbuilding. Marine engineering
Divisions: Faculty of Engineering and the Environment > Civil, Maritime and Environmental Engineering and Science > Fluid / Structure Interactions Research
ePrint ID: 345814
Date Deposited: 06 Dec 2012 11:46
Last Modified: 27 Mar 2014 20:27
URI: http://eprints.soton.ac.uk/id/eprint/345814

Actions (login required)

View Item View Item

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics