Posters

Abstract

The atmospheric stratification, caused by the daily cycle of the surface heating and cooling, impacts a lot on the wind profile extrapolation to the hub heights in wind resource assessments. The atmospheric stratification modeling with computational fluid dynamics (CFD) methods is developed in some advanced CFD software like Meteodyn WT. The different atmospheric stratification determination methods have been validated in the simple site, Cabauw. This work aims to investigate the method applications in a complex site. In Meteodyn WT, three approaches can be used to determine the thermal stability according to the data availability. The MOST theory requires the temperature measurements for two different heights, which are rare in the standard measurements. In the absence of the temperature measurements, a calibration approach, which compare the measured wind profiles and the CFD simulated wind profiles to determine the thermal stability, can be applied for all type of the site. Svenningsen [1] proposes a novel approach to quantify atmospheric stability in the absent of temperature measurement, which is validated on a simple site in Cabauw. The objective is to compare these three approaches in a complex site. It is shown that the calibration approach and Svenningsen's approach distinguish seasonal and daily variations of thermal stability in complex site. However, the MOST theory approach necessaries a high quality of temperature measurements with a precision of ±0.1°. [1] L.Svenningsen, René M.M.Slot and Morten L. Thogersen, A novel method to quantify atmospheric stability, Journal of Physics: Conf.Series (2018)