Al-Nahrain Journal for Engineering Sciences

The study here under describes the impact of adding a nano-scaled ceramic particles on the mechanical and fatigue behaviors of aluminum matrix composites AMCs containing 0.5 ,1.0 ,1.5, and 2 % wt. of nano-scaled B4C and Al2O3 particles were dispersed in molten aluminum by the stir-casting process. Vickers, tensile, and fatigue devices were utilized to evaluate the mechanical behavior of composites in the fabrication process. The results show that increasing the weight percentage of nano-ceramic particles increased the hardness, maximum tensile stress, and fatigue strengths of the base alloy. Furthermore, all of the above behaviors of AMCs reinforced with B4C particles are better than those of AMCs reinforced with Al2O3 particles.

Abstract
The experimental analysis was conducted under the Iraqi climate conditions to investigate the performance enhancement of a solar updraft tower system (SUTS) using porous copper foam as an absorber plate and a conventional absorber plate with an absorber inclination angle of 18°. In the present work, a semicircular collector was divided into two identical quarter thermal collectors to become two identical SUTS. One of the quarter circular thermal collectors contains the metal foam as an absorber plate, while the other quarter collector is on the conventional flat copper absorber plate. In this study, the air inlet height is changed at (3, 5, and 8) cm. The experimental tests were carried out in Baghdad city (latitude 33.3° N). Results showed that the air inlet height variation caused to enhance the solar updraft tower performance. The highest values were recorded when the air inlet height is 3 cm using a porous absorber compared to a flat absorber plate. Copper material foam as an endothermic surface causes a marked decrease in the average surface temperature of the plate. The maximum hourly thermal efficiency of the solar collector was increased to about 41.6 % and the maximum enhancement of the power output to about 45.2 % compared with the flat absorber plate.

In recent decades, many factors have emerged in the building design field, as the technology development after the industrial revolution has left many environmental problems affecting building environments and turning them into unhealthy ones. Also, the issues of consuming natural resources required innovative and modern solutions to address, which needed the guidance and focus of researchers, engineers, and many other relevant disciplines to find the best treatments to solve them. One of the essential treatments was using advanced smart technology to solve the environmental problems of buildings, such as providing thermal comfort and reducing energy consumption.
The concept of adaptive smart envelopes is one of this manifestation of advanced technology in the field of building design characterized by interaction and adaptation to the surrounding environment through the application of many technologies which it works to improve its environmental efficiency. The research aim was to simulate the changes in the building environment, which is treated by covering the building with an adaptive smart envelope by using the Rhinoceros Grasshopper programme.