Modern solar power plants concentrate heat from the sun’s rays into a central receiver from thousands of mirrors. Current heat transfer fluids (HTF) that are employed to transfer this heat to a thermal storage medium or to the working fluid of a power cycle are limited to operating below 820K, thereby limiting the cycle thermodynamic efficiency. One possible route to enhancing system efficiency is the use of a flowing particle medium composed of ceramic particles. Ceramic particles are relatively inexpensive and can withstand higher temperatures (~1300 K) and can be handled like a fluid.
However, the constitutive laws for dense granular flow remain a matter of debate. Our research seeks to gather benchmark heat transfer and flowfield data for flow in complex geometries, such as tube banks likely to form part of a heat exchanger. In particular, we are interested in the effects of wall roughness, and cylinder arrangement on heat transfer.