Measurements of flow past simulated sinusoidal hills were taken in an atmospheric boundary layer wind tunnel (ABLWT) that modeled typical full-scale complex terrain for many wind turbine locations in the Altamont Pass, California, USA. Velocity profiles and speed-up factors for several model hills were determined. All hills modeled had the same height and sinusoidal cross-section, and length-to...

We analyzed intermittency in the solar wind, as observed on the ecliptic plane, looking at magnetic field and velocity fluctuations between 0.3 and 1 AU, for both fast and slow wind and for compressive and directional fluctuations. Our analysis focused on the property that probability distribution functions of a fluctuating field affected by intermittency become more and more peaked at smaller ...

Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the nminute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuation...

CL, CD, CD0 = lift coefficient, drag coefficient, and drag coefficient with zero lift DSi = dynamic soaring number sample E, Emin = aircraft total energy and minimum sustainable total energy, J g = gravity acceleration, m∕s h, hmin = altitude and safety altitude, m K = drag-polar-induced drag gain k1, k2, k3 = necessary and sufficient conditions inequality parameters L, D = lift and drag forces...

Wing-in-Ground Effect vehicle (WIG-craft) or ekranoplane landing direction optimization criteria is suggested which heeds the irregular sea waves features and provides the minimal mechanical strain on the vehicle body at hydrodynamic braking. The problem of automatic choice of the landing trajectory direction regarding the main direction of sea waves spread is under consideration. The peculiari...

through this article, the distribution of air pollutants in tehran have been simulated based on wind patterns with and without the presence of synoptic by tapm (a meso-scale model). the simulation covers three horizontal resolution domains 30, 15 and 5 kilometers. the pollutants chosen for this are co and pm10 and wind data is 10 meter height level. the result has shown that the model simulated...

Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this L...

This paper explores the method of assessing regional spatial ventilation performance for the design of residential building arrangements at an operational level. Three ventilation efficiency (VE) indices, Net Escape Velocity (NEV), Visitation Frequency (VF) and spatial-mean Velocity Magnitude (VM), are adopted to quantify the influence of design variation on VE within different regional spaces....