Investigation and Measurement of Copper Nanofluid Impact on Thermal Efficiency of Solar Collectors

This study compared the impacts of using copper nanofliud to enhance the
efficiency of flat solar collectors with closed loop and under forced convection heat
transfer circumstances to traditional work fluids. Various concentrations of nanoparticles
in water and water/glycol, from 250ppm to 3000ppm, were examined for volume fraction
impact. Results indicate that the laboratory tests were different from those under real
conditions because of the high concentration of nanoparticles used in laboratory tests;
however, by using nanofluid (even with low concentrations around 0.3%) solar collector
efficiency improved (3.2%).Results have also shown that the use of copper nanofluid in
ethylene glycol as the base fluid causes a significant reduction in collector efficiency, due
to the increase in viscosity. However, using higher flow rates caused the heat transfer rate
to rise because of increased turbulence.