Enhancement of Thermal Performance of Wickless Heat Pipe Solar Collector with Surfactant Added Nanofluid

Abstract

There are various sources of renewable energy and solar energy is one of the most cleaner forms of the available resources. The solar collector is a well-established technology having few limitations. The solar collector has various applications like water heating, space heating and cooling, etc. However, thermal efficiency of these type of collectors is limited by working fluid absorption properties. The main limitations of conventional solar collectors are the pump and its power requirement, night cooling due to reverse flow of cooled water, space required is more for obtaining the natural circulation of working fluid, limited heat carrying capacity of working fluid, and pipe corrosion. An alternative solution to the above problems is the Heat pipes. Currently, the usage of nanofluid, which is basically liquid- nanoparticles colloidal dispersion as a working fluid in wickless heat pipe has been found to enhance solar collector efficiency. An experimental study has been performed for investigating the thermal performance of heat pipe solar collector which uses the circular heat pipes with working fluid as TiO2-H2O nanofluid in addition with surfactant (Olic acid). The effect of volume concentration of TiO2-H2O nanofluid in wickless heat pipe and mass flow rate of water on performance of flat plate solar collector has also been investigated.