Application of the thermal diode concept for the utilization of solar energy

This paper introduces a number of numerical and experimental investigations to harness the Sun´s energy using the thermal diode concept. Three different types of thermal diodes are constructed and tested following the numerical simulation to verify their actual performance and adaptability (feasibility). Of these, the first model is a simple thermal diode consisting of a number of rectangular loops whose direction of heat transfer can be easily manipulated either manually or automatically. The second model consists of a rectangular fluid reservoir, a vertical cavity and an inclined channel connecting the reservoir and cavity. This design is easy to construct and very effective in transporting and storing heat for space heating in winter. The concept employed in the second model could be further extended to build a solar water heating system with a tubeless flat plate collector. An antifreeze solution is circulated through the system by natural convection extracting heat from the solar energy to heat the water contained in a separate storage tank