WIND LOADS ON SQUARE CYLINDER IN HOMOGENEOUS TURBULENT FLOWS

This research project studies the turbulence effects on the wind load characteristics on a 2D square cylinder through wind tunnel model tests. The controlled parameters are turbulence intensity and length scale ratio. Total of 27 flow conditions are studied to identify the individual effect of each turbulence characteristic on wind force coefficients and force spectra. Experimental results indicate that the mean drag coefficient, Cd, decreases with respect to turbulence intensity. The fluctuating drag coefficient, Cd', increases with enhancement of turbulence intensity. The rms lift coefficient, C(l)', stays invariant to the change of turbulence intensity but exhibits a significant trend of decrease with the increase of length scale ratio. Both turbulence intensity and length scale ratio are used as the basic parameters to derive the empirical models of alongwind admittance function and the acrosswind spectra.