Effect of Al2O3 and MgO nanofluids in heat pipe solar collector for improved efficiency

In this work, a heat pipe solar collector (HPSC) utilization system is proposed. An experimental system was designed to analyze the effect of nanofluid concentration on the efficiency of the solar collector. The HPSC system was investigated with low concentration of water-based Al2O3 and MgO as the working medium. To examine the structural and optical properties, the X-ray diffraction (XRD) and Fourier transform-infrared (FT-IR) were performed. The HSPC exhibited higher efficiency when they treated with MgO nanofluids. As the concentration of the nanofluid increases, the efficiency of the solar collector is increased irrespective of the working medium. Nevertheless, compared to the Al2O3, MgO reported superior efficiency irrespective of the concentration. Second, the entropy generation for MgO was lower and highest for the neat water. Further, the flow rate of the nanofluids increases the collector efficiency spikes. Experimental system shows that the maximum performance of the HPSC is possible by employing the nanofluids to the existing system in an optimized concentration.