Gust occurrence in simulated non-stationary winds

An investigation is presented of peak gust intensity in non-stationary winds of different durations, in which the non-turbulent component of the event is fully controlled. A typical downburst was simulated repeatedly using a technique that utilizes a parametric analytical model of the downburst's non-turbulent winds, and an amplitude-modulated Gaussian stochastic process for the turbulent component. The peak gust strength of each event was expressed as a peak factor in relation to the largest non-turbulent speed. The properties of the simulated downburst peak factors are compared with those of stationary events of varied duration. A parametric study in which the non-turbulent component of the wind was simulated using a sine wave, which can be related to a downburst through the use of a “storm period” (SP) parameter, was conducted. A range of SP and turbulence amplitude modulation factors were used, and the properties of the peak factors are discussed.