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Design of a high intensity ultrasound dispersion cell

Includes bibliographical references.

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Bibliographic Details
Main Author: Foster, Clinton
Other Authors: Tapson, Jonathan
Format: Thesis
Language:English
Published: Department of Electrical Engineering 2015
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access_status_str Open Access
author Foster, Clinton
author2 Tapson, Jonathan
author_browse Foster, Clinton
Tapson, Jonathan
author_facet Tapson, Jonathan
Foster, Clinton
author_sort Foster, Clinton
collection Thesis
description Includes bibliographical references.
format Thesis
id oai:open.uct.ac.za:11427/13916
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:31:38.662Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2015
publishDateRange 2015
publishDateSort 2015
publisher Department of Electrical Engineering
publisherStr Department of Electrical Engineering
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/13916 Design of a high intensity ultrasound dispersion cell Foster, Clinton Tapson, Jonathan Mortimer, Bruce Electrical Engineering Includes bibliographical references. The aim of this project was to provide detailed research on the factors causing mechanical damage in a high power ultrasound environment, and to give recommendations for the production of an ultrasonic dispersion cell with a removable treatment vessel. The primary mechanism for causing this dispersion was cavitation: a void of air or vapour in a liquid medium that grows and collapses in an intense ultrasonic sound field. The secondary mechanism was a phenomenon called acoustic streaming which provides a macro mixing effect, also caused by intense ultrasound. Streaming and, even more so, cavitation were difficult to measure and for this reason a refinement of a method to map cavitation fields with aluminium foil was developed. This involved using digital image processing to extract quantitative information from damaged foil samples. A large portion of the project focused on the overcoming of absorption and subsequent rapid attenuation of sound between the transducer (ultrasonic source) and the treatment vessel. This absorption was due to a number of interrelated factors: reflection of sound at material boundaries; cavitation clouds causing sound scattering; energy absorption; and conventional absorption in liquids due to viscous damping. A number of strategies were employed to overcome this absorption problem: the use of increased static pressure to suppress cavitation in certain areas; the use of multiple transducers; and, as a result, multiple paths for the sound to enter the vessel. A combination of static pressure and multiple transducers were also tested. A number of different media were tested for their ability to transmit sound and an optimum solution was recommended. Streaming and the physical constraints affecting streaming in the treatment vessel were tested to give a practical guide to the factors producing streaming. Then, as the temperature of the liquid affects absorption, cavitation threshold, and the ability of a solvent to dissolve, a look at the thermal aspects of the system was discussed. 2015-09-15T10:02:43Z 2015-09-15T10:02:43Z 2003 Master Thesis Masters MSc http://hdl.handle.net/11427/13916 eng application/pdf Department of Electrical Engineering Faculty of Engineering and the Built Environment University of Cape Town
spellingShingle Electrical Engineering
Foster, Clinton
Design of a high intensity ultrasound dispersion cell
thesis_degree_str Master's
title Design of a high intensity ultrasound dispersion cell
title_full Design of a high intensity ultrasound dispersion cell
title_fullStr Design of a high intensity ultrasound dispersion cell
title_full_unstemmed Design of a high intensity ultrasound dispersion cell
title_short Design of a high intensity ultrasound dispersion cell
title_sort design of a high intensity ultrasound dispersion cell
topic Electrical Engineering
url http://hdl.handle.net/11427/13916
work_keys_str_mv AT fosterclinton designofahighintensityultrasounddispersioncell