Two-way coupled aerodynamics and vehicle dynamics simulations of a heavy ground vehicle subjected to crosswind of various frequencies

Abstract

The present study investigates the dynamic characteristics of a heavy ground vehicle subjected to crosswind with various frequencies using two-way coupled simulations between aerodynamics and vehicle dynamics, including the driver’s steering inputs. Four different reduced frequencies of crosswind, which are equal to 4.2, 2.1, 1.3 and 0.9, are used. The results show that the absolute maximum magnitudes of the vehicle’s lateral dynamic and aerodynamic characteristics increase inversely proportional with the reduced frequencies of crosswinds without the driver’s steering input. However, when the driver’s steering input is included in the vehicle’s response to the crosswind disturbances, the vehicle’s lateral dynamic characteristics increase by the largest amount for reduced frequencies of 1.3 and 2.1. Furthermore, for a reduced frequency of 0.9, the driver’s steering inputs attenuate the unfavourable amplifications in the vehicle’s lateral dynamic characteristics. In the present study, the reasons for the increase in the vehicle’s lateral dynamic characteristics in the cases of reduced frequencies equal or greater than 1.3 with the driver’s steering input are explained. Additionally, the results show that the vehicle is not controlled within the 0.5 m lateral margins of the road when the steering starts with a time delay of 1.0 s for reduced frequencies equal to or lower than 2.1.