Experimental Study Of Generalized Logarithmic Law For High-order Moments At High Reynolds-number

First of all, taking a 50m high meteorological tower located at the southeastern edge of the Badain Jaran Desert of China as the research object, this study conducts FLUENT simulations and analysis on the distorting influence of the tower structure on the flow field around it. Results show that the attenuation of the wind in the lee wake of the tower agrees well with the existing field observations and wind tunnel experiments which verify the accuracy of the numerical simulations in this study. Simulation-based analysis is performed with particular concentration on the streamwise, lateral and vertical components of the tower-induced wind velocity errors on the windward side. It shows that the reduction ratio of the streamwise wind velocity varies with the azimuth angle θ of the tower-mounted anemometers yielding a Gaussian distribution. When θ=±55° the distorting effect is not significant regardless of the incoming wind velocity and the distance from the tower. For the lateral components, the tower-induced velocities increase with the incoming streamwise wind velocity, and the maximum tower-induced wind velocity can reach 15% of the inlet streamwise wind velocity respectively.The results provide a reference for instrument setup of field observation experiments.Then,using experimental datasets which were got from observing systems located at southeast edge of the Badain Jaran Desert,this paper analyses the ’generalized logarithmic law’ for high-order moments at high Reynolds number and the slope Ap whether is dependent on the Reynolds number,and compares with the laboratory results by Meneveau and Marusic (2013).It shows that:At high Reynolds-number and low Reynolds-number, the results are consistent with a ’generalized logarithmic law’; For higher order-moments(2p=4,6,8,10), the coefficient Ap increases with increasing Reynolds number and the higher order-moments the more obvious; At high and low Reynolds-number, the results displays’sub-Gaussian statistics’ and it has a weak dependence of the Reynolds-number.