A. Baradaran Rahimi - Mechanical Engineering, Ferdowsi University of Mashhad
A. Kianifar - Mechanical Engineering, Ferdowsi University of Mashhad

In this paper, a model for closed loop solar system is presented and an attempt is made to generalize the model to be utilized for primary design of any solar active thermal system. This model may be used for systems in which gas or a liquid are fluids that flow. Two new parameters, namely, the system heat delivery factor and the system heat absorption factor are introduced in the model. These two factors are fully discussed and some equations are developed for their determination.

Solar Heating System, Solar Radiation, Closed Loop