An experimental study was conducted to investigate the effects of relative rotation direction on the wake interferences among two tandemwind turbines models. While the oncoming flow conditions were kept in constant during the experiments, turbine power outputs, wind loads acting on the turbines, and wake characteristics behind the turbines were compared quantitatively with turbine models in eit...

the urban heat island effect refers to the temperature rise of the cities in comparison to the suburbs. this phenomenon which is a consequence of urbanization and has become a major issue in the urban climatology may have serious consequences in the developing countries which are facing a rapid and unplanned urban growth. tehran, the capital and the most populated city of iran, this phenomenon ...

In this paper authors focus on determination of the threshold velocity of re-suspension for particles 10 m in an urban street canyon with two-way traffic. The urban wind threshold velocity of re-suspension is derived from a long-term measurement carried out in the city of Brno. A numerical modelling based on the finite volume method is used for a detail study of the relation between a wind velo...

A Doppler lidar system for wind velocity and direction measurement is presented. The lidar use a wide field of view (FOV) objective lens as an optical antenna for both beam transmitting and signal receiving. By four fibers coupled on different position on the focal plane, the lidar can implement wind vector measurement without any scanning movement.

The study of interactions of jet into cross flow at different longitudinal and transverse angles of jet was studied. The following components were designed and constructed: a low velocity wind tunnel to produce the uniform flow, a flat plate with a traverse injection system to simulate the jet injection, and a spatial rake to measure the total pressure. The tests were carried out at longitudina...

Wind regime and sand grain size are two of the factors that determine the morphology and dynamics of sand dunes in desert areas. Regarding the importance of wind effects on sand dunes especially in Iran, in this study, Khartooran Erg was analyzed to determine wind direction and to detect sand source sites. Khartooran Erg is located on eastern north of Iran and lies in Khorasan Razavi and Semnan...

We extend the functionality of a low-cost CW diode laser coherent lidar from radial wind speed (scalar) sensing to wind velocity (vector) measurements. Both speed and horizontal direction of the wind at ~80 m remote distance are derived from two successive radial speed estimates by alternately steering the lidar probe beam in two different lines-of-sight (LOS) with a 60° angular separation. Dua...