An Experimental Investigation of Parabolic Trough Collector Using Industrial-Grade Multiwall Carbon Nanotube (MWCNT) - H2O Based Nanofluid

Solar thermal systems for heating have a high level of reliability. The usage of parabolic trough collectors (PTC) for domestic applications is still quite limited; furthermore, commercial utilization of nanofluids in these applications is rare. The influence of MWCNT nanofluid as a heat transfer fluid on the efficiency of a locally developed parabolic trough collector was examined experimentally. The effect of surfactant on nanofluid stability was also investigated, and it was revealed that nanoparticles could be evenly suspended in base fluid for at least 10 days and less than one month using Triton X-100. Experiments were also conducted to determine the optimal quantity of Triton X-100 surfactant; it is possible to make nanoparticles stable for 28 days in base fluid with the ratio of Triton X-100 to MWCNT as 0.5:1. At 2.0, 3.0, and 4.0 L/min flow rates, MWCNT/H2O is used at three-particle concentrations of 0.1 %, 0.2 %, and 0.3 % by weight. The experiment is carried out under outdoor operating conditions. With 3 L/min at 0.2 wt. %, MWCNT nanofluid achieves a maximum thermal efficiency that is 22 % greater than the water. The findings provide important information about the commercialization of a locally developed PTC.