Published Online:May 2024
Product Name:The IUP Journal of Mechanical Engineering
Product Type:Article
Product Code:
Author Name:Prem Kumar S and T Venkate Gowda
Availability:YES
Subject/Domain:Engineering
Download Format:PDF
Pages:16
The paper proposes a solar collector with sensible heat storage materials for crop drying applications. The materials used were pebbles and gravels. The experiments were conducted under the meteorological conditions of Ujire, Karnataka, India. The bed thickness of pebbles and sand was 20 cm, and air velocity for pebbles and sand as absorbers was 4 m/s and 2 m/s. The experiments were started at 9 o’clock and stopped at 17 o’clock; for every one-hour interval, readings were recorded. Experimental and theoretical heat transfer analyses were carried out and the results were discussed with the help of characteristic curves. The collector with pebbles as absorber showed better performance than the collector with sand as absorber. This is due to surface roughness and higher Reynold’s number. The maximum theoretical and experimental values of temperature resulted for pebbles were 344 K and 321 K, and for sand 334 K and 322 K, respectively. The average theoretical efficiency obtained with pebbles as absorber was 39%, and for sand 28.5%. The average value experimental efficiency with pebble as absorber was 25%, and for sand 11%. The developed collector system with pebbles and sand as absorber provides moderate temperature heat and is best suited for drying of crops.
Solar energy is a freely available and clean source of energy. Most parts of the earth receive approximately 3,850,000 Exa-Joules per year (IEA, 2014) for more than 280 to 300 good sunny days. The present and future energy need of the world can be effectively met by harnessing this freely available energy. Solar drying is one of the important applications of solar energy, which is used to dehydrate the products, and the products can be stored for longer duration without bacterial and fungal growth.