The material used for the study is bi-axial glass cloth with epoxy resin. Two sets of laminates were manufactured using vacuum assisted resin transfer moulding, one laminate with parent material (P1, P2) and the other laminate with graphene platelet nanopowder (P1-GPN, P2-GPN). For the graphene platelet nanopowder samples, addition of 0.1% weight of graphene platelet nanopowder is mixed with epoxy resin. Three different tests such as tensile, compression and impact were conducted on the composite material. There was an increase of 11.18% and 33.4% in tensile strength, 26.4% and 24.6% in compression strength when compared to the parent samples of 2 and 3 mm thickness, respectively. This strength was obtained with the reduction of fibre content when compared to other research works. Also high-velocity impact test using gas-gun method was performed on parent and blended samples. The energy absorption levels of blended samples were 9.2% and 8.2% higher than the parent samples of 2 and 3 mm thickness, respectively. Therefore, this study reveals that the addition of graphene platelet nanopowder with the parent material has increased the strength of the composite tremendously.

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This research work attempts to study the most prominent factor of the drilling operations performed on different thicknesses of biaxial glass fibre reinforced with graphene platelet nanopowder and epoxy composite using three different drills. Damages are induced in the workpieces to analyse the effect of changed cutting parameters and different tool materials for varied thicknesses of the plates during the drilling process. The resultant drilled hole exhibited surface irregularities that are measured using SURFCOM 1400G. The circularity deviations of the holes are measured using a coordinate measuring machine. Image-processing technique is used to calculate the area of maximum diameter of the damaged zone. Using these data, delamination at entry and exit is calculated. Utilizing response surface methodology and grey relational analysis, the varied operations are carried out and analysed with different tool materials for common cutting parameters. It is found that the lesser thickness workpiece with selected HSS drill under high speed and low feed rate is the best variable option.

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Energy consumption has increased withthe population increase, and fossil fuel dependency has risen and causing pollutions. Solar energy is suitableto provide society's thermo-electric needs. Thermal energy storage-based concentrated solar receivers are aimed at store heat energy and transportable to the applications. Acavity receiver with two-phase change materials (PCM) is experimentally investigated using a parabolic dish collector to act as the solar heat battery. The selected PCMs are MgCl2.6H2O and KNO3-NaNO3. PCMs are chosen and placed as perthe temperature zones of the receiver. The outdoor test wasconductedto determine the conical receiver's storage performance using cascaded PCMs. The complete melting of PCM attainsat an average receiver surface temperature of 230°C. The complete melting of the PCM in the receiver took around 30 minutes at average radiation around 700 W/m2, and heat stored is approximately 5000 kJ. The estimated number of cavity receivers to be charged on a sunny day is about 10-15 according to the present design and selected PCMs, for later use