Development and experimental investigation of new self-can cooling systems

Abstract

In this thesis, two conceptual self-cooling beverage can designs are proposed. The methods of cooling are validated experimentally and certain parameters of interested are obtained for an analytical and numerical study of the conceptual designs. Optimization of the can geometry for heat transfer rate, volume of beverage, and total amount of cooling is performed. Experiments are carried out using experimental test systems that evaluate the validity of two specific cooling methods. First method of cooling uses ammonia throttling followed by desiccant salt adsorption. The results show that there is satisfactory cooling for 300 ml of water in 3 minutes. The second method uses an endothermic reaction between ammonium thiocyanate and barium octahydrate as a cooling method. The results show that this method is also a valid cooling method. The experimental work provides key parameters of interest for the analytical and numerical study of the proposed conceptual self-cooling can designs. The numerical study is conducted using computational fluid dynamics and heat transfer modeling. The goal of this study is to determine the best aspect ratio for the cooling vessel inside the beverage can, and to determine the effects of ambient temperature on the performance of the system. The results show that the best performing aspect ratio is aspect ratio 4. Aspect ratio 4 is the thinnest and longest cooling vessel and provides the best heat transfer performance. Ambient temperature does not significantly change the final temperature of the beverage at the end of 3 minutes. A cooling effectiveness study is conducted to evaluate the performance of the self-cooling beverage can. The study only looks at the ammonia expansion design. The best performance in terms of cooling effectiveness is achieved when using aspect ratio 4 at an ambient temperature of 35°C. The cooling effectiveness for this specific case is 0.834 for energy and 0.772 for exergy, respectively. An optimization study of the self-cooling beverage can geometry is conducted. The objectives are to minimize cooling time, maximize volume of beverage, and maximize cooling effectiveness. The non-dominating optimal solutions are presented in Pareto front graphs. The results of this study provide a highly effective tool needed to make a decision on which dimensions to use in a final design of a self-cooling beverage can.