Surface roughness is one of the key quality parameters of the finished product. During any machining operation, high temperatures are generated at the tool-chip interface impairing surface quality and dimensional accuracy of products. Cutting fluids are generally applied during machining to reduce the temperature at the tool-chip interface. However, the usages of cutting fluids give rise to problems such as waste disposal, pollution, high cost, and human health hazard. Researchers, nowadays, are opting toward dry machining and other cooling techniques to minimize the use of coolants during machining while keeping the surface roughness of products within desirable limits. In this paper, a concept of using Peltier cooling effects during aluminium milling operation has been presented and adopted with an aim to improve the surface roughness of the machined surface. Experimental evidence shows that Peltier cooling effect provides better surface roughness of the machined surface compared to dry machining.

Since the events at the Fukushima-Daiichi nuclear power plant, there has been increased interest in developing accident tolerant fuel (ATF) to better withstand accidents for current light water reactors where Uranium-Silicide based fuel has a good field to withstand the hydrogen hazards. In the same way, steel cladding is also the center of attraction for researchers nowadays. In this study, the feasibility of using uranium-silicide having different compositions (i.e., U₃Si, U₃Si₂, U₃Si₅) combined with different types of austenitic steel (i.e., AISI) is investigated to improve the safety performance. A 3D CFD coded STAR CCM+ model was used in assessing the performance of heat transfer in the hexagonal fuel assembly of a supercritical water-cooled reactor VVER-1200. Utilizing the computational environment and the flexibility of STAR CCM+ code the test analysis was conducted using the realizable K-Epsilon Two-Layer Wall turbulence model. Results from this analysis also showed that the combination of U₂Si₃ fuel with AISI-348 should get superiority over conventional fuel-claddings assemblies to use in the reactor core of VVER-1200 because of their lower central fuel temperature value in the analysis and good mechanical and thermal advantages. These results also provide valuable data to guide future works about the thermal analysis of the VVER -1200 reactor core to support the relevant examinations and for choosing the best heat transfer equations.

Indoor physical exercise has been a trend nowadays. This is due to their limited time to go outside and do exercise. Many people are doing physical exercises in the gymnasium. A large amount of wasted kinetic energy is created by a human from the equipment in gymnasia such as treadmills, bicycles, and rowing machines. These kinds of exercise machines produce a huge amount of wasted energy from vibration and rotation. The modern challenge facing the global energy situation is the increasing demand for energy and the strong dependence on unsustainable fossil fuels. This project discussed the transformation of mechanical energy from the vibration of the treadmill machine to electrical energy by collecting it using piezoelectric materials. Piezoelectric materials were possible to harvest energy from vibration. Piezoelectric tiles 6" (152.4 mm) and 8" (203.2 mm) were created to harvest the waste energy from the treadmill machine due to high vibration. The vibrations were produced due to the impact of the runner on the treadmill machine. The piezoelectric tiles were placed under the treadmill machine and the high voltage obtained was value. The voltage obtained varied depending on a deflection on tiles. High voltage can be obtained by arranging the piezoelectric material based on the localization of distributed stress on the tile. It was also obtained that the series connection of more electrical energy from the vibration, it is discovered that the series connection of piezoelectric sensor was the factor of high ratio of electrical energy production.

Surface roughness is one of the widely used parameters for assessing the quality of the finished products. The Surface profile of the machined product is influenced by the variation of the vibration amplitude resulted from the system components. Vibration during milling operation affects the surface roughness as well as the quality of the component and tool life which indirectly increases the component cost. An attempt has been made to send an anti-phase frequency signal from the center of the machined surface during machining processes. Different types of frequency have been applied in the center point of the workpiece and its effect was investigated in the surface roughness responses. The focus of the study is to investigate the effect of vibration frequency on surface roughness in both preheated and normal conditions during end-milling operations. From the experimentation, it has been observed that with the increase of frequency the surface roughness improved in both the conditions of preheated and normal machining processes. The final analysis of variance revealed that the best surface roughness condition is achieved at preheated conditions compared to normal machining processes.

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