Sharif Digital Repository

Nowadays, a wind tunnel is a tool used in aerodynamic research to study the effects of air moving past solid objects. By employing a wind tunnel, we can compeletely control the conditions of aerodynamic testing on specific models. In this research, the design of a diffuser for the subsonic wind tunnel has been taken into account by CFD. The wind tunnel is of suction type and is powered by three axial fans which are manufactured by LTG Inc. The tunnel test section has a 140 cm height and 195cm width which can provide a necessary Mach number. Considering the setting of the three axial fans, located at the end of the diffuser and parallel to each other, it’s necessary to take into consideration... 

By developing composites, difficulties of modeling of degradation of properties as stiffness is most considered. The recent advances in the modeling of degradations in stratified composites have led to improved models on all scales. Macro scales methods are good to estimate fracture but not to estimate the failure in micro scale (as microcrack) and moreover, they need many experimental data. Therefore by considering a stratified structure which contains fiber, matrix and intermediate area, mesoscale modeling method is most suitable. In this research Micromechanical Progressive Algorithm (MPA) is used. The method employed is Micromechanic Method of Fracture (MMF). In this work by developing a...