R. L. Sawhney

EXPERIMENTAL PERFORMANCE OF BUILT-IN-STORAGE SOLAR WATER HEATING SYSTEMS IN LABORATORY AND FIELD CONDITIONS

Hourly thermal performance (both in laboratory and field conditions) of three designs of built-in-storage solar water heating systems of 100 litres capacity each has been reported. A different storage tank design is used in each of the three cases. Design I consists of three tanks connected in series; in Design II, a parallelepipedic tank is divided into five zones with baffles; Design III is a simple parallelepipedic tank. The first two designs help in inducing thermal stratification in the tank. It is seen from the results that the performance of Design II is the best of the three.

Sizing of a multi‐tank solar water heater

The thermal performance of a multi-tank solar water heating systems under different climatic conditions, has been characterised by the solar fraction i.e. the fraction of needed energy, available from sun. An earlier model of Sodha et al. (1984) has been validated with experimental observations on different models of solar water heating systems. This model and the concept of solar fraction have been used to size the system for different climatic regions of country represented by Jodhpur (hot and dry), Srinagar (cold), Bombay (warm and humid), Mount Abu (cool), Delhi (composite) and Bangalore (moderate).