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This research work is an experimental study focusing on the thermophysical properties of water/EG based hybrid nanofluid suspended with CuO and Al2O3 nanoparticles. The main objective of the study is to investigate the effect of volume concentration and temperature on the thermal conductivity and dynamic viscosity of water/EG based hybrid nanofluid. The CuO-Al2O3 (50:50) nanoparticles were dispersed in the base fluid at a volume concentration between 0.25– 1.0%. The thermal conductivity and dynamic viscosity of the nanofluid were experimented with at a temperature ranging between 30–70°C. The hybrid nanofluid with 1% concentration of CuO-Al2O3 nanoparticles was found to be the most stable nanofluid with a zeta potential of -35.1 mV. Meanwhile, the increase in CuO-Al2O3 nanoparticle volume concentration increases the thermal conductivity of base fluid by almost 8.67% at a temperature of 70°C. The increase in volume concentration of nanoparticles increases the dynamic viscosity of the base fluid, while the increase in temperature significantly reduces the viscosity of CuO-Al2O3 hybrid nanofluid. The proposed nanofluid has good potential to be used in the convective heat transfer application. [ABSTRACT FROM AUTHOR]

High demands on flexibility, lighter weight, thinner size and low-cost electronic product had increased the application of Flexible Printed Circuit Board (FPCB) over Rigid Printed Circuit Board (RPCB). However, the thermal factor affects FPCB significantly during the reflow soldering process. The temperature of the reflow soldering process causes the FPCB to encounter significant deflection and thermal stress compared to the RPCB. Therefore, the present experiment investigates the effect of temperature on FPCB layout during the reflow soldering process. The deformation of RPCB and FPCB was measured using a KEYENCE LK-G152 laser sensor placed at the entrance and outlet of the reflow oven. Two temperature profiles were used as a variable for the experiment: soaking temperature profile and ramp temperature profile. The investigation shows that component placements pattern influences the deformation of FPCB. The FPCB component placements reduce the deformation due to low wetting angle and component weight. FPCB solder joint has a good wetting angle (<90°), indicating good solder paste deposited on the FPCB. However, several solder joints on FPCB are irregular in shape due to high deformation. Therefore, it is essential to study the effect of temperature on FPCB during the reflow soldering process for industries guideline for mass production of FPCB products. [ABSTRACT FROM AUTHOR]

Precipitation hardening is a heat treatment process to increase the strength of aluminum alloys with solution heat treatment, quenching and aging processes. This literature study aims to determine how aging from the precipitation hardening process affects aluminum zirconium alloy material on mechanical properties with varying temperature and aging time. The analysis was carried out using secondary data obtained from research published before in various journals. The research material is aluminum zirconium alloy with 0.1-0.4% zirconium composition and above 99.5% aluminum composition. The temperatures used in this study were 375°C, 400°C, and 425°C, and the aging time was up to 400 hours. Based on studies from various literature, it is found that the aging process gets an increase in the hardness value of aluminum alloy materials. The results of this study will be one of the references in further research. [ABSTRACT FROM AUTHOR]

Wind turbines are power plants that utilize renewable energy. One of the essential parts in the development of wind turbines is the blade component. This study aims to compare the strength of wind turbine blades from bamboo composite materials with wind turbine blades using GFRP material. The data used in this study uses secondary data obtained from research that has been published in various journals. The research was carried out with software-assisted loading simulation. The strength of the blades is simulated using loads of 17.65 N, 20.59 N, and 22.555 N. Based on the simulation results, it can be concluded that the wind turbine blades made of bamboo fiber composite material have good strength. At light loads, the value of yield strength, shear strength, and safety factor can exceed the strength of water turbine blades made of GFRP. Wind turbine blades made of bamboo fiber composites have good potential to replace wind turbine blades made of GFRP. [ABSTRACT FROM AUTHOR]

Renewable energies, specifically solar energy which is the richest renewable energy on earth, has been employed in numerous applications due to the fact that it is pollutant-free, widely available and inexhaustible. The main thrust of this study is to predict thermal and electrical efficiencies of photovoltaic-thermal (PV/T) setups in regard with load power and solar radiation by developing an adaptive neuro fuzzy inference system (ANFIS) and multiple linear regression (MLR) models. To achieve this goal, about 266 empirical measurements were performed on two different fabricated PV/T setups (conventional PV and a water-cooled PV/T system). Several statistical analyses were carried out to assess and validate the proposed models. Base on the results obtained, it was confirmed that there was an excellent agreement between the predicted model outputs and the actual experimental data. However, the ANFIS model outperformed MLR model due lowest MSE with a value of (19.500 for PV/T thermal efficiency, 0.0440 for PV/T electrical efficiency and 0.0021 for PV electrical efficiency). In addition, the lowest RMSE (4.4158 for PV/T thermal efficiency, 0.2097 for PV/T electrical efficiency and 0.0089 for PV electrical efficiency) and the highest correlation of determination (R2) (0.9003 for PV/T thermal efficiency, 0.9972 for PV/T electrical efficiency and 0.9998 for PV electrical efficiency) respectively. [ABSTRACT FROM AUTHOR]