Wind tunnel modelling of neutral boundary flow over mountains

Abstract

Wind tunnel experiments have been carried out in the 12m wide by 4m high working section of the 1.5MW wind tunnel at Monash University to measure turbulent wind flow downstream of a 1/200 scale model of a 334m high mountain. Three component wind velocities, turbulence intensities and Reynolds shear stresses have been measured behind the mountain with the approaching neutral boundary layer flow of a tunnel gradient wind speed 10ms-1 to study flow interactions with topography. The wind flow was found to have separated on the leeward side of the mountain around the two sides and over the top causing significant flow distortion and orographical induced turbulence. These changes due to the flow separation in the wake region of the mountain can have further impact on the wind-induced response of structures downstream. Finally some measured data are included for the wind flow characteristics behind a similar mountain model of a smaller geometric scale of 1/1500 for comparison.