soghra mohammadzadeh

Three airfoils NACA0015, NACA0018 and NACA0021 were selected and in the Q-Blade software, the coefficients of shear, post and the maximum ratio of the exponential coefficients were determined and, finally, the Airfoil Nakata 0015 at a speed of 5 and 10 meters per second, was selected and best. Fluent software was used to solve it, based on the finite volume method. For numerical analysis, the turbulence method K-ω SST was validated with experimental results. The wind turbine schematics was designed in Catia software and the height of the blades was 35 and 75 centimeters, the radius of the blade was 18.5 cm and the length of the airfoil 6.4 Cm is. The results show that in order to operate the turbine of porous blade windings at 35 cm height at speeds of 1, 2, 3, 4, 5, 7, 7.45, 8.25, 8.5 m / s 50% 50%, 33%, 50%, 50%, 60%, 57%, 55%, 50%, and for setting up a porous blade wind turbine at a height of 75 cm at a speed of one, two, three, four, Five, seven, 7.45, 8.25, 8.5, 9, 9.5 m / s 66.6%, 75%, 80%, 71.4%, 66.6%, 76.9%, 80%, 82%, 89%, 100% of the launching force Smooth wind turbine is required at the same height.

The The wind turbine converts the kinetic energy of the wind current into the rotational energy of the rotor shaft. The use of vertical axis wind turbines as a source of clean energy production is of great importance. Among the advantages of vertical axis wind turbine over horizontal axis wind turbine are low production cost, lightweight, the efficiency of the installation, and use in residential zones. The darriues blades of vertical axis wind turbines are more in the kind of straight or helical blades. The central difficulty of Darius vertical axis wind turbines is their primary self-starting, which is the basis of this study. They increase self-initiation at low speeds. For this purpose, Darius vertical axis wind turbine was designed and built-in CATIA software. NACA0015 is made for airfoils and the material used for straight and porous blades is plain aluminum sheet and porcelain embossed sheet, both of which are series alloys of aluminum and the equipment used in manufactured and calibrated Manufacturing and calibrating. The result showed that the Ambas blade wind turbine needs less torque to start up to a speed of 9m/s than the vertical blade axis wind turbine.

Over the past years, two-dimensional materials such as graphene, phosphorene, silicene, and boron-nitride have attracted the attention of many researchers. After the successful synthesis of graphene, due to its many new applications, researches began to produce nanosheets from other elements, and among these elements, boron was one of the options. In the periodic table of elements, boron is ahead of carbon and after beryllium, which exhibits metallic and non-metallic properties. The two-dimensional boron sheets called borophene are one of the allotropes of this element that reaches their stable and single-layer structure by forming triangular lattice and the carbon like SP2 hybridization. Since boron is carbon’s neighbour, so it is expected that two-dimensional boron sheets would have properties close to graphene. Here, we investigate the wettability of the borophene mono-layer surface by calculating contact angle of the water and the surface of the sheet by using the molecular dynamics simulation method. According to the measurements obtained from this simulation, the contact angle is approximately 131 degrees, indicating that such a structure is hydrophobic. Also, the effect of diameter of nanodroplet on the surface contact angle has been studied.