Heat transfer coefficient of a snow bag
- Authors: Da Veiga, Willem Richter
- Date: 2014-09-10
- Subjects: Heat - Transmission , Dry ice , Refrigerated transport , Snow bag
- Type: Thesis
- Identifier: uj:12226 , http://hdl.handle.net/10210/11993
- Description: 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%.
- Full Text:
- Authors: Da Veiga, Willem Richter
- Date: 2014-09-10
- Subjects: Heat - Transmission , Dry ice , Refrigerated transport , Snow bag
- Type: Thesis
- Identifier: uj:12226 , http://hdl.handle.net/10210/11993
- Description: 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%.
- Full Text:
Key challenges in the outbound pharmaceutical cold chain
- Authors: Kosmas, Sarantis
- Date: 2016
- Subjects: Business logistics , Refrigerated transport , Drugs - Equipment and supply
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/237630 , uj:24349
- Description: M.Com. (Logistics Management) , Abstract: The South African pharmaceutical cold chain industry has a fundamental challenge in balancing the quality requirements, driven by the Medicines Control Council (MCC), within a constrained revenue model that caps the possible income from distribution activities through single exit pricing (SEP) regulations. This research seeks to understand the key challenges in the pharmaceutical cold chain industry. Through the use of a survey and cost analysis, both a qualitative and quantitative view of the research on the outbound distribution operations for fine distribution, distribution to pharmacies and hospitals, of cold chain pharmaceuticals were obtained. The research takes a structured approach to identifying relationships between various elements of the pharmaceutical cold chain, as well as ascertaining the key factors and risk ratings of these elements. This information was analysed to identify the key challenges in the pharmaceutical cold chain industry. Using the Lambert and Stock total cost model, a framework was developed to guide both the survey and cost analysis research. As both components were structured in this manner, these components could be cross-referenced for consistency. The findings of the research identified that there was a significant relationship between the outbound distribution and the quality elements of the supply chain. The most important key factors were determined to be transportation volume, product write-offs, cold room validation, duration of the cold chain packaging system, type of temperature monitoring equipment, and cold room and freezer storage. The key risks were identified as being in the transport, validation/qualification and cold chain packaging elements. The research concluded that quality elements related to the warehousing function are well controlled, while the highest risk is within the transportation element. The research successfully identified six key challenges all related to the transportation element of the pharmaceutical cold chain industry. These challenges related to cold chain packaging, temperature monitoring as well as validation/qualification of cold chain packaging systems.
- Full Text:
- Authors: Kosmas, Sarantis
- Date: 2016
- Subjects: Business logistics , Refrigerated transport , Drugs - Equipment and supply
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/237630 , uj:24349
- Description: M.Com. (Logistics Management) , Abstract: The South African pharmaceutical cold chain industry has a fundamental challenge in balancing the quality requirements, driven by the Medicines Control Council (MCC), within a constrained revenue model that caps the possible income from distribution activities through single exit pricing (SEP) regulations. This research seeks to understand the key challenges in the pharmaceutical cold chain industry. Through the use of a survey and cost analysis, both a qualitative and quantitative view of the research on the outbound distribution operations for fine distribution, distribution to pharmacies and hospitals, of cold chain pharmaceuticals were obtained. The research takes a structured approach to identifying relationships between various elements of the pharmaceutical cold chain, as well as ascertaining the key factors and risk ratings of these elements. This information was analysed to identify the key challenges in the pharmaceutical cold chain industry. Using the Lambert and Stock total cost model, a framework was developed to guide both the survey and cost analysis research. As both components were structured in this manner, these components could be cross-referenced for consistency. The findings of the research identified that there was a significant relationship between the outbound distribution and the quality elements of the supply chain. The most important key factors were determined to be transportation volume, product write-offs, cold room validation, duration of the cold chain packaging system, type of temperature monitoring equipment, and cold room and freezer storage. The key risks were identified as being in the transport, validation/qualification and cold chain packaging elements. The research concluded that quality elements related to the warehousing function are well controlled, while the highest risk is within the transportation element. The research successfully identified six key challenges all related to the transportation element of the pharmaceutical cold chain industry. These challenges related to cold chain packaging, temperature monitoring as well as validation/qualification of cold chain packaging systems.
- Full Text:
- «
- ‹
- 1
- ›
- »