It is well-known that wind farm noise is dominated by low-frequency energy at large distances from the wind farm, where the high frequency noise has been more attenuated than low-frequency noise. It has also been found that wind farm noise is highly variable with time due to the influence of atmospheric factors such as atmospheric turbulence, wake turbulence from upstream turbines and wind shea...

The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield. To better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process would be beneficial. Here, a technique developed at The University of Texas at Austin that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalen...

High tall buildings are more susceptible to dynamic excitations such as wind and seismic excitations. In this paper, design procedure and some current applications of tuned mass damper (TMD) were studied. TMD was proposed to study response of 20 storey height building to seismic excitations using time history analysis with and without the TMD. The study indicates that the response of structur...

Windmill, machine that converts wind into useful energy. This energy is derived from the force of wind acting on oblique blades or sails that radiate from a shaft. The turning shaft may be connected to machinery used to generate electricity. The present paper makes an attempt to show the effect of wind and earthquake load on tubular type windmill and its foundation considering hard, medium and ...

The main contributing factors to unsteady loading of Offshore Wind Turbines (OWT) are wind shear, turbulence, and waves. In the present paper, the turbulence intensity and the wind shear exponent are investigated. Using data from the FINO 1 research platform, these parameters are analyzed and compared with the proposed wind field parameters in the IEC standard 61400-3. Based on this analysis, a...

UCHIYAMA, Y., 2007. Hydrodynamics and associated morphological variations on an estuarine intertidal sand flat. Journal of Coastal Research, 23(4), 1015–1027. West Palm Beach (Florida), ISSN 0749-0208. Hydrodynamics, sediment suspension, and morphological response on an estuarine intertidal sand flat in Tokyo Bay, Japan, are examined through a field experiment performed for 16 days in winter 20...

[1] Results of an experimental investigation of the turbulent boundary layer in airflow over evolving young wind-waves are presented. The experiments were conducted in a laboratory wind-wave flume consisting of a closed-loop wind tunnel capable of generating wind speed that may exceed 15 m/s, atop of a 5 m long wave tank. Simultaneous measurements of mean wind velocity and of instantaneous fluc...

Cosmic shear holds great promise for a precision independent measurement of Ω m , the mass density of the universe relative to the critical density. The signal is expected to be weak, so a thorough understanding of systematic effects is crucial. An important systematic effect is the atmosphere: shear power introduced by the atmosphere is larger than the expected signal. Algorithms exist to extr...

The spectral width observed by Doppler radars can be due to several e€ects including the atmospheric turbulence within the radar sample volume plus e€ects associated with the background ̄ow and the radar geometry and con®guration. This study re-examines simple models for the e€ects due to ®nite beamwidth and vertical shear of the horizontal wind. Analytic solutions of 1and 2-dimensional models ...

Helicity was calculated in Hurricane Bonnie (1998) using tropospheric-deep dropsonde soundings from the NASA Convection and Moisture Experiment. Large helicity existed downshear of the storm center with respect to the ambient vertical wind shear. It was associated with veering, semicircular hodographs created by strong, vortex-scale, radial-vertical flow induced by the shear. The most extreme v...