Transient behaviour of collector/storage solar water heaters for generalised demand patterns

This communication presents a simple transient model for predicting the thermal performance of collector/storage solar water heaters for generalised demand patterns. These heaters consist of either (i) an insulated rectangular metallic tank whose top surface is blackened and suitably glazed (i.e. a built-in storage solar water heater) or (ii) an insulated open shallow tank with black bottom.inner sides and a glass plate at the surface in contact with the water (i.e. a shallow solar pond water heater). The time dependence of the water temperature for the withdrawal of hot water from the system at constant flow rates constantly or intermittently has been explicitly evaluated. Numerical results for the operation of the system in industrial and community service applications are discussed.