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 enhance the safety of current light water reactors. Uranium-silicide based fuels have shown promise in withstanding hydrogen-related hazards. Similarly, steel cladding has become a key focus for researchers.

In this study, the feasibility of using uranium-silicide fuels with different compositions (i.e., U₃Si, U₃Si₂, U₃Si₅) in combination with various types of austenitic steel (i.e., AISI grades) was investigated to improve safety performance. A 3D CFD model using STAR-CCM+ was employed to assess heat transfer performance in the hexagonal fuel assembly of a supercritical water-cooled VVER-1200 reactor. Leveraging the computational flexibility of STAR-CCM+, the analysis was conducted using the realizable K-Epsilon Two-Layer Wall turbulence model.

The results indicated that the combination of U₂Si₃ fuel with AISI-348 steel outperforms conventional fuel-cladding assemblies for use in the VVER-1200 reactor core. This combination exhibited lower central fuel temperatures and favourable mechanical and thermal properties. These findings provide valuable data for guiding future studies on the thermal behavior of the VVER-1200 reactor core and support the selection of optimal heat transfer models for reactor safety analysis.

Indoor physical exercise has become a popular trend nowadays, mainly due to people’s limited time to go outside for workouts. Many individuals exercise in gymnasiums, where a large amount of wasted kinetic energy is generated by equipment such as treadmills, stationary bicycles, and rowing machines. These machines produce significant vibrational and rotational energy that typically goes unused.

One of the modern challenges in the global energy landscape is the rising energy demand and the heavy reliance on unsustainable fossil fuels. This project explores the conversion of mechanical energy from the vibration of a treadmill into electrical energy using piezoelectric materials. Piezoelectric materials can harvest energy from mechanical vibrations.

To achieve this, piezoelectric tiles of sizes 6" (152.4 mm) and 8" (203.2 mm) were fabricated to capture waste energy produced by treadmill vibrations caused by the runner’s impact. The tiles were placed under the treadmill, and a measurable voltage output was obtained. The generated voltage varied depending on the deflection of the tiles. Higher voltages were achieved by strategically arranging the piezoelectric materials based on the distribution of stress across the tile surface.

It was also found that connecting multiple piezoelectric sensors in series significantly increased the electrical energy output, making series configuration a key factor in enhancing overall energy generation efficiency.

This research focuses on the design and development of a leak detection and monitoring system for the third generation of pressurised water reactors. The system is based on an integrated sensor unit consisting of humidity, vibration, and ultrasonic sensors that can monitor the real-time condition of pipeline degradation and service ageing. The goal is to enable maintenance or replacement before any loss of safety function occurs.

The leak-before-break (LBB) concept is well established in nuclear power reactors, particularly in water-cooled systems. It is based on the premise that a detectable leak develops before a catastrophic rupture occurs. This research aims to enable early detection of leakage and, when leakage is detected, to identify its key properties—such as leak size, location, direction, and loose part movement—through detailed data analysis from the vibration sensor.

Each integrated sensor unit employs three types of sensors to minimize false signals. The vibration sensor monitors pipeline conditions and detects cracks or leaks. The humidity and temperature sensors verify leakage signals from the vibration sensor to reduce false alarms. Finally, the ultrasonic sensor monitors pipeline bending and displacement caused by high-pressure fluid leakage.

Through these combined measurements, the system can comprehensively monitor the pipeline’s behavior and detect abnormalities ranging from small internal cracks to complete pipeline failures.

Surface roughness is one of the most widely used parameters for assessing the quality of finished products. The surface profile of a machined component is influenced by variations in vibration amplitude resulting from the system’s components. Vibration during milling operations affects not only surface roughness but also the overall quality of the component and tool life, which in turn increases manufacturing costs.

In this study, an anti-phase frequency signal was applied from the center of the machined surface during the machining process. Different frequencies were introduced at the center point of the workpiece, and their effects on surface roughness were investigated. The primary objective was to examine the influence of vibration frequency on surface roughness under both preheated and normal conditions during end-milling operations.

Experimental results showed that as the frequency increased, surface roughness improved under both preheated and normal machining conditions. The final analysis of variance (ANOVA) revealed that the best surface finish was achieved under preheated conditions compared to normal machining.

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