Measurement of hygrothermal performance of an evaporatively cooled, double walled enclosure with cement and lime mortar/plaster.
The objective of this work is to extend and test the idea of a clay-pot refrigerator to building applications. Clay-pot refrigerators have been used for a long time to store vegetables and other perishable items in hot-dry climates. The refrigerator consists of a clay pot within a larger clay pot. The space between the pots is filled with sand and water. Due to the diffusion of water through the outer pot, the contents of the inner pot are cooled. The amount of cooling depends on the outdoor conditions and the geometrical configuration. The proposed work tries to extend the same idea by making double walled scaled models of a room/space which could be used for human comfort. Depending on the measured performance the concept can be employed for constructing spaces such as community centres, public booths, cabins, exposed walls of houses, etc. This passive technique can produce a comfortable indoor climate as compared to the outdoor. Fans could be used to provide air circulation and distribute the cooling effect. Figure 1 shows a schematic of the experimental set-up based on the idea of a clay pot refrigerator. The amount of cooling can be measured by monitoring variables such as indoor temperature, relative humidity and surface temperatures as a function of outdoor conditions. The study aims to quantify the actual cooling effect and explore the evaporative cooling potential of such a space. Moreover, two identical models, one with cement and other with lime mortar/plaster will be constructed and monitored to compare the performance and role of lime and cement in evaporative cooling. This work will also explore the above concept as a separate wall system for passive cooling of building spaces.
