Show simple item record

dc.contributor.advisorOlley, Peter
dc.contributor.advisorCoates, Philip D.
dc.contributor.authorMulvaney-Johnson, Leigh*
dc.date.accessioned2011-08-01T16:53:46Z
dc.date.available2011-08-01T16:53:46Z
dc.date.issued2011-08-01
dc.identifier.urihttp://hdl.handle.net/10454/4983
dc.description.abstractThe gas assisted injection moulding process is an important extension to conventional injection moulding. Gas assist can be applied in a number of ways, but here the penetration of a gas bubble through the polymer melt is of interest. A 3D fi nite element implementation of a pseudo concentration method is employed to simulate the primary penetration of the gas bubble. The wall thickness prediction is an important result since the extent of bubble penetration is sensitive to the remaining melt fraction. A number of methods for experimental measurement are developed to measure characteristics of the gas assisted injection moulding process dynamics and product. Key process variables, on an industrial gas-assist machine, were measured and analysed, leading to an empirical model for wall thickness prediction. Gas delay time and injection velocity are shown to be most influential in controlling residual wall thickness. Simulation results are evaluated against the empirical model. The trends observed, for simulation and experiment, in wall thickness after changes in process variable settings are found to agree qualitatively. The wall thickness prediction is found to be within 10% of the experimentally obtained measurements.en_US
dc.description.sponsorshipEPSRC
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>.en_US
dc.subjectGas assisted injection mouldingen_US
dc.subjectSimulationen_US
dc.subjectGas bubble formationen_US
dc.subjectWall thickness predictionen_US
dc.titleGas assisted injection moulding: Experiment and simulation. Industrial machine experimental studies of the effect of process variables on gas bubble formation, and with simulation based upon a pseudo-concentration method.en_US
dc.type.qualificationleveldoctoralen_US
dc.publisher.institutionUniversity of Bradfordeng
dc.publisher.departmentDepartment of Mechanical and Medical Engineeringen_US
dc.typeThesiseng
dc.type.qualificationnamePhDen_US
dc.date.awarded2001
refterms.dateFOA2018-07-19T06:25:00Z


Item file(s)

Thumbnail
Name:
Mulvaney_Johnson_phd_thesis_co ...
Size:
2.384Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record