Temperature Distribution and Evaporation Rate in Porous Media

Abstract

Various studies have been done to improve solar still performance, especially in water streams. Various methods create thin water flow on the absorbent plate, including using porous media. The research aims to identify temperature distribution and evaporation rate in porous media. The use of porous media as an absorber plate material in solar still applications is investigated in this study. Five types of porous media have been researched, such as concrete consisting of river sand and iron with a particle size of 0.125 and 0.250 mm, and natural stone. A comparison of 5 specimen types is held by conducting evaporation tests. The pore media specimen 5x1x10 cm is heated by an electric heater with a power of 36, 4 W. The bottom side of the specimen is exposed to a constant high salt water reservoir. Data is collected periodically for 2 hours. Research produces specimens at smaller particle sizes with thermal conductivity and greater heat transfer rates. Iron sand concrete as aggregate has better temperature distribution than the specimen of river sand. The largest high-dampened front reduction is obtained on specimen C with a value of 0.051 m. The largest evaporation rate is owned by specimen C with the amount of 2.38 ml in 7200 s. Concrete with an aggregate of iron sand (0.125 mm particle size) is recommended as a solar still absorbent plate material; however, natural stone materials also have a high potential to be used as a solar still absorbent plate material.