M.Ing. (Mechanical Engineering) / In snow shooting, pressurised liquid carbon dioxide is injected via a lance into a permeable snow bag mounted near the ceiling of an insulated transport container. The decrease in pressure causes the liquid carbon dioxide to convert to "snow" and vapour inside the snow bag. The snow bag acts as a phase separator, allowing the sublimated snow to cool down the products inside a container. In this thesis the heat transfer coefficients of such a snow bag were determined experimentally and theoretically. It was found, that on average the measured heat transfer coefficient was 31% lower than the theoretical prediction. The theoretical model was used to correlate the experimental heat transfer coefficient as function of snow height. With this correlation it was possible to predict the time of the snow life to within 24%.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uj/uj:12226 |
| Date | 10 September 2014 |
| Creators | Da Veiga, Willem Richter |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
| Type | Thesis |
| Rights | University of Johannesburg |
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