Investigation of combination of heat storage container and thermosyphon solar system in existence of nanomaterial

Abstract

This research explores the combination of fins into thermosyphon solar collectors to enhance energy efficiency. The storage system includes a finned container filled with nanomaterial (a blend of Al2O3 nanoparticles and paraffin (RT30)), while the fluid circulating within the tube consists of a homogeneous mixture of copper nanoparticles and water. Unsteady laminar flow within a three-dimensional domain, incorporating gravitational forces, has been modeled. The numerical approach has undergone rigorous validation, demonstrating strong agreement with both experimental and numerical data. Effects of fin installation and nano-powder dispersion have been investigated across various scenarios. At t = 60 min, the liquid fraction (LF) is approximately 2.08 times higher in the system with fins compared to the simple case. LF progressively increases over time, reaching a value 3.1 times higher at t = 60 min compared to t = 30 min. The temperature of the nanofluid in the tank rises over time. Despite the enhanced nanofluid temperature in the tube due to fin presence, a decrease occurs within the domain due to accelerated melting rate in the container. Incorporation of nanoparticles into paraffin shows an improvement in LF by approximately 11.66 % in the presence of fins.

Keywords

• Evacuated solar system
• Paraffin container
• Nanoparticles
• Unsteady modeling
• Extended surfaces