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The present study numerically investigates the optimization of thermal performance in a dimpled channel using a promising genre of nanofluid which is equipped with the inclusion of two-dimensional (2D) MXene (Ti3C2) nanoparticles to the soybean oil. The stream-wise and span-wise variation of the spherical dimples was kept 3.00 and 3.15 over the flow domain with an elongation of 2.5 mm. The detailed evaluation of both the local and global parameters is carried out for 0.025%, 0.075%, and 0.125% mass concentrations of MXene. The Reynolds number is varied from 1000 to 6000 to understand the effect of both the laminar and turbulent flow characteristics in predicting the thermal performance. The simulations are carried out using finite volume method (FVM) under constant heat flux, assuming the mixture of nanoparticles as homogeneous mixture. The results show that with the increase in the mass concentration of nanoparticles, thermal performances of the nanofluid increase. However, it is also identified that with the increase in Reynolds number, the thermal performance increases under turbulent flow regime. On the contrary, thermal performance was observed to be decreased with the increase in Reynolds number under laminar flow regime. An astounding improvement in 88.9% thermal performance is found for 0.125% mass concentrations of soybean-based MXene nanofluid which exclusively indicates the credibility of MXene nanofluid as a next generation potential candidate for heat exchanger industries.

In this research work, novel hybrid graphene-silver (Gr-Ag) nanomaterial has been used for first time with paraffin wax as a phase change material (PCM) to improve its thermo-physical properties. Thermal and electrical energy efficiencies of the novel synthesized nanocomposite (PCM/graphene-silver) has been investigated in solar thermal collector systems (CPV/T). This paper focuses on preparation, characterization, thermo-physical properties and energy efficiency in concentrated photovoltaic/thermal (CPV/T) system of new class of nanocomposites induced with hybrid Gr-Ag nanomaterial in three different concentrations. The specific heat capacity (cp) of hybrid PCM/graphene-silver nanocomposite increased by introducing hybrid Gr-Ag nanomaterial. Electrical and thermal energy performance of the hybrid PCM/graphene-silver is investigated in a CPV/T system using MATLAB 2017b program. The improvement of cp is found to be ~ 40% with 0.3 mass% of hybrid Gr-Ag nanomaterial loaded in PCM. The highest thermal conductivity increment is found to be ~ 11% at 0.3 mass% concentration of hybrid Gr-Ag nanomaterial in PCM. The endothermic enthalpy value of the hybrid PCM/graphene-silver nanocomposite is found to be ~ 75.6 J g−1 at 0.1 mass% loading concentration of hybrid Gr-Ag nanomaterial. Melting point of hybrid PCM/graphene-silver nanocomposite with loading concentration of 0.3 mass% is measured to be 73.2 °C. The highest thermal efficiency using the hybrid graphene-silver nanoparticles reached the value of 39.62% which represents 4.16% increment in comparison with the pure PCM. The equivalent electrical efficiency is improved by 2.8% at the loading concentration of 0.3 mass% of the hybrid Gr-Ag nanomaterial. These new class of nanocomposites represented the capability of enhancement in the performance of the CPV/T system consisting of lower PV temperatures, higher temperature gains across the cooling fluid and higher electrical and thermal efficiencies.

In this research work, MXene with a chemical formula of Ti3C2 is used for the first time with silicone oil to improve thermo-physical properties of MXene based silicone oil. This paper focuses on preparation, characterization, thermal properties, thermal stability and performance investigation of new class of silicone oil nanofluids induced with MXene in three different concentrations for a Concentrated Solar Photovoltaic Thermal (CPVT) collector. The thermal conductivity of the silicone oil-based MXene nanofluids is measured using a Transient Hot Bridge (THB) 500. Viscosity is measured using a Rheometer at various temperatures including 25, 50, 75, 100, and 125 degrees C. PerkinElmer Lambda 750 is used to measure optical absorbance. The highest thermal conductivity enhancement is found to be 64% for 0.1 wt% concentration of silicone oil-MXene nanofluid compared to pure silicone oil at 150 degrees C. The viscosity of MXene with silicone oil nanofluids is found to be independent of addition of MXene nanoparticles in the silicone oil base fluid. Viscosity is reduced by 37% when temperature is raised from 25 degrees C to 50 degrees C for different concentrations of MXene with silicone oil. Silicone oil-based MXene nanofluid with 0.1 wt% concentration is thermally stable up to similar to 380 degrees C. Introducing more MXene nanoparticles into silicone oil improves electrical efficiency of PV module due to better cooling of MXene based nanofluids. Higher solar concentration is resulted in higher average temperature of the PV module. This consequently raises thermal energy gain which is useful for different applications.