in this study, aerodynamic characteristics of a circular cylinder in an axial flow have been investigated numerically and experimentally. the model has been considered as a cylinder with truncated nose and fineness ratio of 3 (length to diameter ratio of 3). the investigation involves a series of wind tunnel measurements, flow visualization, and numerical simulation. we used different mach numb...

A shrouded wind turbine system has a number of potential advantages over the conventional wind turbine. A novel power-augmentation-guide-vane (PAGV) that surrounds a Sistan wind turbine was designed to improve the wind rotor performance by increasing the on-coming wind speed and guiding it to an optimum flow angle before it interacts with the rotor blades. The integration of the PAGV into the 3...

Tornadoes are violently rotating columns of air extending from thunder storms to the ground. While extensive studies have been conducted to assess wind loads and flow structures around building models in strong winds, most of the previous investigations were conducted with straight-line winds. Bienkiewicz and Dudhia (1993) found that the wind loads acting on building models in tornado-like wind...

Atmospheric boundary layer wind tunnels (ABLWTs) have been used for 40 years to simulate the interaction of the wind and earth in the lowest few hundred meters of the atmosphere. ABLWTs are well-suited for investigating flow in complex terrain and have different strengths and weaknesses than numerical modeling. There are a wide variety of applications, including performing wind resource assessm...

Due to their size, small rotorcraft are vulnerable to external flow disturbances that are challenging to flight stability and control. This paper describes preliminary results from using onboard flow measurements to augment inertial sensors for attitude control. We derive a dynamic model that captures the aerodynamic effects of wind on a single degree-of-freedom tandem-rotor test stand. A pair ...

One of the main architectural characteristics in the central area of Iran is the relation between life and climatic conditions; e.g., the four-seasonal house which is a typical kind of the central-yard house. As the climate of Isfahan is more pleasant than other desert regions in the central part of Iran, wind towers are replaced with skylights to ventilate the pool area of hoze-khane. So far, ...

natural ventilation is one of the best and the cheapest methods of ventilation that is accomplished by production of natural air flow inside of building. in iran traditional architecture, natural ventilation had been an important part of building designing but nowadays wind energy optimum usage has disregarded because of buildings congestion. rasht in gilan province is placed in a moderate and ...

An experimental study was conducted to investigate the dynamic wind loads acting on a wind turbine model sited in atmospheric boundary layer winds. The experimental studies are conducted in a large-scale Aerodynamic/Atmospheric Boundary Layer (AABL) Wind Tunnel available at Iowa State University. A three-blade Horizontal Axial Wind Turbine (HAWT) model was placed in atmospheric boundary layer w...

The enhancement in the penetration of intermittent generation necessitates the need to include uncertain behaviour in the conventional power flow programs. In this paper, four different wind generation models have been incorporated in probabilistic load flow for calculating the probability distribution of the reactive power consumed by the wind generators for three different scenarios; i) uncor...

During the month-long METCRAX field campaign in northern Arizona near Winslow in October 2006, observed wind profiles uncovered a frequent presence of a nearsurface wind maximum on nights with relatively quiescent synoptic conditions. The development of this flow usually began shortly after sunset with a shift from disorganized wind directions accompanying weak winds in late afternoon to a more...