The objective of this work was to assess the accuracy of various coupled mesoscale-microscale wind flow modeling methodologies for wind energy applications. This is achieved by examining and comparing mean wind speeds from several wind flow modeling methodologies with observational measurements from several 50 m met towers distributed across the study area. At the mesoscale level, with a 5 km r...

An experimental study was performed to examine the wake characteristics and aeromechanic performance of an innovative twin-rotor wind turbine (TRWT) in comparison with those of a conventional single-rotor wind turbine (SRWT). The comparative study was conducted in a large-scale Aerodynamic/Atmospheric Boundary Layer (AABL) wind tunnel with the TRWT and SRWT model sited in simulated atmospheric ...

The “Leipzig Wind Profile” is a unique example of a representative wind distribution in the frictional layer which resulted from MILDNER’S set of 28 pilot-balloon observations with two theodolites on October 20, 1931, near Leipzig for a stable weather situation. It is shown, that the vectors of geostrophic motion and ground drag follow from the wind profile when a scalar austausch is assumed. T...

In this paper, a self-adaptive flange is proposed for the wind turbine shrouded by a flanged diffuser to reduce the wind loads acting on the flanged diffuser at high wind velocities. The self-adaptive flange can maintain the advantages of the flanged diffuser at wind velocities lower than the rated velocity and reduce the wind loads acting on the diffuser and blades at higher wind velocities. N...

by John A. Cooney, Jr. In order to e↵ectively realize future goals for wind energy, the e ciency of wind turbines must increase beyond existing technology. One direct method for achieving increased e ciency is by improving the individual power generation characteristics of horizontal axis wind turbines. The potential for additional improvement by traditional approaches is diminishing rapidly ho...

With the increasing penetration of wind energy into power system, wind energy conversion systems (WECSs) should be able to control the power flow for limited as well as maximum power point tracking. In contrast to the traditional pitch angle control, this paper focusses on field oriented speed control of permanent magnet synchronous generator (PMSG) for controlling the active power flow based o...

Wind-flow pattern over embankments involves an overexposure of the rolling stock travelling on them to wind loads. Windbreaks are a common solution for changing the flow characteristic in order to decrease unwanted effects induced by the presence of cross-wind. The shelter effectiveness of a set of windbreaks placed over a railway twin-track embankment is experimentally analysed. A set of two-d...

Abstract: A set of idealized cloud-permitting simulations is performed to explore the influence of small islands on precipitating convection as a function of large-scale wind speed. The islands are situated in a long, narrow ocean domain that is in radiative-convective equilibrium (RCE) as a whole, constraining the domain-average precipitation. The island occupies a small part of the domain, so...

An experimental investigation was conducted to assess the effectiveness of a suction flow control method for vortex-induced vibration (VIV) suppression. The flow control method uses a limited number of isolated suction holes to manipulate the vortex shedding in the wake behind a circular cylinder in order to reduce the unsteadiness of the dynamic wind loads acting on the cylinder. The experimen...

Given the significant rise of the utilization of wind energy the accurate assessment of the wind potential is becoming increasingly important. Direct applications of wind assessment techniques include the creation of wind maps on a local scale (typically 5-20 km) and the micrositing of wind turbines, the estimation of vertical wind speed variations, prospecting on a regional scale (>100 km), es...