solar water heater; transparent insulation; mild winter
In this paper, the design of a triangular built-in storage-type solar water heater with transparent insulation on the top and sides is studied under various operating conditions. The transient performance of the system is studied by using a finite-difference forward time-step marching technique. The thickness of the transparent insulation is also optimized for the best performance of the system. The numerical results for mild winter conditions in Delhi show that the system with transparent insulation performs better than conventional water heater with movable insulation.