الملخص الإنجليزي
Abstract :
As far as ground vehicle lateral stability is concerned, aerodynamics in gusty crosswind conditions is significant factor in the vehicle development process as well as bridge design and construction. Recent investigations have demonstrated that unsteady aerodynamic loads can exceed steady loads considerably which may decrease driving lateral stability and may lead to loss of handling control. In order to compute and evaluate the vehicle's response to crosswind gusts, it is essential to determine the aerodynamic excitation on the vehicle body. The present work is concerned with the lateral dynamic stability of ground vehicles while crossing bridges during severe, gusty crosswind conditions. In this investigation, Shaikh Isa bin Salman Bridge is considered, due to its geometrical construction properties with regard to side wind pulse generation, as an example of gusty crosswind conditions. In severe windy days, vehicles are exposed to disturbing and experiencing a pulsating crosswind while crossing the bridge. This may lead to the driver feeling that there is reduced control over the vehicle. Several accidents have been reported in local newspapers which are related to loss of lateral control in vehicle. This study focuses on the crosswind modelling of the bridge to find the variation of the aerodynamic distribution pattern at various crosswind velocities and orientations and their effect on the stability of driver-vehicle closed loop system.
