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Wire-coating and dough mixing are two typical applications from the processing industry, where the complexity of the process may only be resolved by computer modelling. Present day modelling software has developed and is applied widely in such industries, but the nature of this software is limited in its ability to address both complex rheological behaviour (stability problems) and three-dimensional geometrical complexity (efficiency issues). The aim of this project is to develop novel advanced simulation technology to provide the next generation of modelling software capable of addressing these shortcomings. Both the polymer and foods processing industry are currently experiencing fast moving change and innovation, as new materials and potential new application areas are appearing. As a consequence, manufacturing companies which use rheologically complex materials in their products need a better understanding of their processing and its effect on product performance. This then may be related directly to remaining competitive in markets which place a high store on improvements in quality and reductions in cost. The programme of funded industrial work carried out which has led to this application is primarily concerned with the design, manufacture and installation of cables and cable systems for the transmission of information and energy. The markets for such products include traditional conductor wires or cables, and more recently, fibre optic cables through the worldwide demand for information exchange. The ultimate requirement here is to apply polymer coatings to cables as rapidly as possible, with a minimum of polymer material, that will guarantee integrity of the coating when subject to mechanical or thermal stress. Mechanical stress may be built up via physical bending during installation in complex-shaped conduits. Thermal influences will result from applications such as suspending fibre optic communication cables with high voltage electricity transmission lines. Today, there is comparatively little fundamental understanding of the relative importance of process conditions for wire coating. The reason for this is that there are many integrated and diverse aspects involved, such as flow geometry design, material behaviour, production speeds, and cooling. Each of these aspects may have a role to play on the residual stresses frozen into the polymer coating that will have a subsequent effect on product quality. In foods processing the situation is similar. For dough mixing for example, an optimal mixer design and process setting is sought to maximise dough consistency at minimal energy input. Here the process is periodic, the flow is three-dimensional with free surfaces and there is peeling and adhesion to solid surfaces to model.Industrial support for the Institute of non-Newtonian Fluid Mechanics at Swansea has been drawn from both the polymer and foods processing sectors. A major sponsor over the last few years has been BICC Cables, who have supported modelling work associated with the optimisation of the coating of fibre-optic cables or wires. This has encompassed studies of die and process design, to optimise the process conditions and product performance for extruded layers in cable manufacture, taking into account thermal, shear, extensional and memory effects for materials such as polyethylene. BICC Cables have supported this work over the preceding three years, with 44,500 contributed over a two year period from August 1996, 11,167 prior to this in 1996 and have committed to continuation funding (7,442). Foods mixing is a new area to receive this sort of modelling treatment. In this regard, investigation of dough mixing for bread and biscuit manufacture has attracted the support of three separate companies, RHM Technology, United Biscuits and Pillsbury Co, contributing a cash total of 25,000. This area of work involves three-dimensional free-surface flows of a periodic nature, where peeling an
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