Show simple item record

dc.contributor.advisorBenkreira, Hadj
dc.contributor.advisorWhiteside, Benjamin R.
dc.contributor.authorAlpin, Richard P.
dc.date.accessioned2020-12-18T11:41:07Z
dc.date.available2020-12-18T11:41:07Z
dc.date.issued2016
dc.identifier.urihttp://hdl.handle.net/10454/18262
dc.description.abstractCoating onto a moving substrate several films simultaneously on top of each other is a challenging exercise. This is due to the fact, depending on operating conditions (thickness and velocity of individual layers and the physical properties of the coating fluids), flow instabilities may arise at the interfaces between the layers and on the top layer. These instabilities ruin the application of the final multi-layered coating and must be avoided. This research addresses this coating flow situation and seeks to develop guidelines to avoid these instabilities. Following a critical literature survey, this thesis presents a novel experimental method that visualises multi-layered coating flow down an inclined multi-slot die. The visualisation is obtained using a unique configuration including a high-speed camera, telecentric objective lens and illumination. The results show for a single layer, as the die angle and Reynolds number increases, the flow becomes more unstable and for a dual layer flow, as Re increases the peak to peak amplitude and the frequency decreases at the free surface and interface. The latter was unexpected and does not conform with existing literature. The triple layer results show either a monotonically increasing or increasing from first to second layer viscosity stratifications are the most stable flows along with flow heights in the first and second layers of <22% and >18% of the total thickness respectively, which concur with current literature. The visualisation additionally obtained other instabilities including single layer back-wetting and vortices, and multilayer slot invasion with the findings concurring with current literature.en_US
dc.description.sponsorshipEPRSC/Tata Steel Industrial CASE Studentship; EP/J501840/1en_US
dc.language.isoenen_US
dc.rights<a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/"><img alt="Creative Commons License" style="border-width:0" src="http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png" /></a><br />The University of Bradford theses are licenced under a <a rel="license" href="http://creativecommons.org/licenses/by-nc-nd/3.0/">Creative Commons Licence</a>.eng
dc.subjectMultilayer coatingen_US
dc.subjectSlide-dieen_US
dc.subjectCurtain coatingen_US
dc.subjectSlot exiten_US
dc.subjectInstabilitiesen_US
dc.subjectVisualisationen_US
dc.subjectFlow Imagingen_US
dc.subjectFlow visualisationen_US
dc.titleFlow Imaging of the Fluid Mechanics of Multilayer Slide Coating. Flow visualisation of layers formation in a 3-layers slide coating die, measurement of their thicknesses and interfacial and free surface flow instabilitiesen_US
dc.type.qualificationleveldoctoralen_US
dc.publisher.institutionUniversity of Bradfordeng
dc.publisher.departmentFaculty of Engineering and Informaticsen_US
dc.typeThesiseng
dc.type.qualificationnamePhDen_US
dc.date.awarded2016


Item file(s)

Thumbnail
Name:
PhD Thesis_RPALPIN_05006267.pdf
Size:
18.45Mb
Format:
PDF
Description:
PhD Thesis

This item appears in the following Collection(s)

Show simple item record