Study and characterisation of desiccant for thermal heat dissipation properties.
Yap, Hui Ling.
Date of Issue2009
School of Mechanical and Aerospace Engineering
This project aims to cool air by six degrees Celsius using minimal energy. The report includes the background, purpose and scope. Two different approaches were investigated in this report. They were namely the fin cooling technique and the desiccant drying technique. An analysis was done based on the first approach of cooling air using extended surfaces. Commercially available fins with length no longer than 40cm were chosen. Optimal fin spacing calculations were done on the chosen models. The cost of the fin array models selected were analysed and was found to be more costly than ordinary air conditioner unit. Although the fin cooling technique brought about advantages of maintaining moisture of ambient air throughout the entire cooling process, the cost of the fin array was estimated to be much higher than an ordinary air conditioning unit thus making the study unfeasible. The second approach of using desiccant drying and secondary cooling method was discussed in the second half of the report. Experiments were carried out to determine the water vapour adsorptive capacity of superabsorbent polymer. From experiments, it was found that superabsorbent polymer desiccants were able to absorb 27 weight percent of its initial mass of water vapour from air. The theoretical value obtained from calculations overestimates the amount of water vapour absorbed by as much as 14%. The desiccant drying technique was found to be energy efficient as compared to an air conditioning unit. Comparing both the fin cooling technique and the desiccant drying technique, it was found that the latter was more energy efficient with estimates not exceeding 1000 Watts. The report sums up with a chapter on Conclusion and Limitation. The author recommends further studies on placing the desiccant packs at varying positions on all four sides of the test section to observe a further increase in the adsorptive capacity of the desiccant.
Final Year Project (FYP)
Nanyang Technological University