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Titanium dioxide nanofluid is used in the thermosyphon solar flat plate collector at volume fractions of 0.1%, 0.3%, 0.5%, 0.7%, and 1% to test the collector's effectiveness. The heat transfer coefficient, Nusselt number, friction factor, and pressure drop calculations were used to analyze the impact of adding nanoparticles to the working fluid. The effectiveness of the solar flat plate collector and the heat transfer coefficient are both greatly affected by the addition of titanium dioxide to the working fluid, with a tolerable rise in pressure drop. With concomitant variances of 15% and 13%, correlations were constructed for the Nusselt number and friction factor. [ABSTRACT FROM AUTHOR]

The heat transfer and friction characteristics of thermosyphon solar flat plate collector using Al2O3/water nanofluid as working fluid with helical twist insert and its impacts are analysed. Thermal behaviour, heat augmentation and pressure drop characteristics of the modified collector are compared with those of conventional riser tube collector. Alumina nanofluid of 0.1%, 0.3% and 0.5% volume concentrations are used in riser tube of the solar flat plate collector which has helical twist with rod as insert. Correlations for heat augmentation and friction factor in terms of performance parameters like Nusselt number, Prandtl number and fluid concentrations showed acceptable deviations. The convective heat transfer coefficient varies directly with the volume concentration of Al2O3 nanoparticles in base fluid, conversely increasing the fluid concentration increase the density of the nanofluid leading to increase in pressure drop and friction. Results favour to modified nanofluid collector in terms of thermal performance, higher heat removal rate from absorber plate in solar flat plate collector. [ABSTRACT FROM AUTHOR]

Epoxy-based systems serve as excellent adhesives to join a wide range of substrates such as metal, ceramics, plastics, etc. The mechanical properties of such systems can be improved considerably by the addition of filler to the epoxy matrix. Herein, polymethylsilsesquioxane (PMS) and poly(methyl/vinyl)silsesquioxane (PMVS) nanosphere were synthesised by hydrolytic condensation of oraganosilane as a precursor in aqueous phase. The epoxy nanocomposite adhesives were prepared by adding different weight percentages (1–4 wt%) of the PS nanospheres. Tensile and compressive strength of the adhesive formulations were studied using the universal testing machine (UTM) and it was observed that the mechanical properties of the composites showed an increasing trend on increasing the filler loading. Adhesive strength of the epoxy composites on mild steel substrate was studied by conducting the lap shear test and EPV-4 exhibited a 31% increase in adhesive strength on the mild steel compared to the neat epoxy. Surface morphology of the epoxy composites were visualised from the SEM images and the composites also showed enhanced thermal conductivity. Higher mechanical and adhesive strength indicates the potential of the prepared nanocomposites to be used as an effective formulation in adhesive-based systems. [ABSTRACT FROM AUTHOR]