In his research article, several models of heatsink were optimally designed in fin length, width and height along with pin placement which consists of 4 pin fin heatsink models heatsink (including square with different pin angles, circular, truncated cone, and cone pin heatsinks and one model of the plate-fin heatsink (PFHS)) in order to achieve better thermal performance as well as less energy consumption and were numerically investigated under high air velocity and heat fluxes. Different parameters such as peak temperature, Nusselt number, heat resistance, pressure drop, and energy consumption were compared. The results show that the square PPFHS with the pin angle of 45 degrees has the highest thermal performance compared to the rest of the models while also having the highest pressure drop and energy consumption between the models consuming more than 255 and 358 percent more energy in order to have the same air velocity in the pathway, while the truncated and the fully formed cone model despite having 25% and 30% less thermal performance, have the least pressure drop between the pin models of the heatsinks and therefore consume the least energy out of the PPFHS. تفاصيل المقالة

The enhancements in boiling heat transfer can bring immediate benefits to improve the efficiency and cost of heat energy transfer. In this study, heat transfer coefficient in pool boiling of single wall carbon nanotube-water (SWCNTs) at a concentration of 0. 05, 0. 1 and 0. 15 vol. % on smooth and grooved surfaces has been investigated experimentally at atmospheric pressure. The effect of some shapes namely circular groove, square groove and straight groove on the boiling heat transfer has been also investigated. The experimental results indicated that making different grooved surfaces and also using (SWCNTs)-water enhanced the boiling heat transfer coefficient. The highest increase in heat transfer coefficient was seen in circular grooved, which is 76% higher than the base fluid water on the smooth surface. The heat flux has been changed from 0 to 140 kW/m2. By comparing the results, the circular groove with 0.15% concentration of SWCNTs has higher heat transfer coefficient for the boiling heat transfer. Based on pool boiling surfaces, a new type of grooves pool pooling surface was designed and constructed, which is consisted of inclined circular groove at angle of 45°. Outcome of the present work definitely indicates that the inclination of the circular groove could be excellent option for the increasing of pool boiling heat transfer. Cornwel-Houston correlation has been modified to take care of the effect of grooved surfaces for correlating the Nusselt number as a function of Reynolds number and Prandtl number in pool boiling. This new correlation agrees with the experimental data from the augmented surface satisfactory. تفاصيل المقالة

The global scarcity of potable water remains a pressing human challenge, given that 97% of the Earth's water is saline. Therefore, solar desalination that uses cheap solar energy is the best way to prepare fresh water. This study employs a solar desalination apparatus featuring 28 steps, with dimensions of 30 mm in height, 110 mm in width, and 840 mm in length. The present work was conducted to improve and increase this device's efficiency and water output by examining magnetic field impact using 𝐹e3𝑂4 ferrofluid. Also, the ultrasonic phenomenon's effect to increase the device's efficiency is carried out. To increase the daily production rate of fresh water, the mentioned device has been tested and optimized in various configurations including 1) Simple configuration, 2) incorporating magnetic filing sheets, 3) utilizing two solenoids at different turns of 275 and 1000, 4) employing 𝐹e3𝑂4 nanofluid, 5) with 𝐹e3𝑂4 nanofluid and magnetic filing sheets, 6) with 𝐹e3𝑂4 nanofluid, solenoids at different turns of 275 and 1000, 7) involving the ultrasonic phenomenon, 8) utilizing 𝐹e3𝑂4 (Iron (III) Oxide ) nanofluid, solenoids, and ultrasonic phenomenon, experimentally tested and optimized. After examining the results, it was found that mode 8, which includes the combined effect of 𝐹e3𝑂4 nanofluid, solenoid, and ultrasonic phenomenon, had the highest water production rate compared to the simple mode and it could be a cost-effective choice. The device's efficiency from 55.2% in mode 1 has reached 63.4%,72.9%,74.3%,80.2%,87.5% respectively in mode 2,3,5,6, 8 and the basin temperature has reached the highest value of 66.8°𝐶𝐶 at 2 PM in mode 8. According to the test results, it could be concluded that the use of sonicated water with 𝐹e3𝑂4 Ferrofluid under magnetic field effect has led to a significant increase in the device efficiency. تفاصيل المقالة