Coupled analysis of vehicle stability in crosswind on low adhesion road

Abstract

Purpose The purpose of this paper is to develop a two-way coupling approach for investigating the aerodynamic stability of vehicles under the combined effect of crosswind and road adhesion. Design/methodology/approach The author develops a new two-way coupling approach, which couples large eddy simulation with multi-body dynamics (MBD), to investigate the crosswind stability on three different adhesion roads: ideal road, dry road and wet road. The comparison of the results obtained using the traditional one-way coupling approach and the new two-way coupling approach is also done to assess the necessity to use the proposed coupling technique on low adhesion roads, and the combined effect of crosswind and road adhesion on vehicle stability is analyzed. Findings The results suggest that the lower the road adhesion is, the larger deviation a vehicle generates, the more necessary to conduct the two-way coupling simulation. The combined effect of the crosswind and road adhesion can decrease a vehicle’s lateral motion on a high adhesion road after the disappearing of the crosswind. But on a low adhesion road, the vehicle tends to be unstable for its large head wind angle. The vehicle stability in crosswind on a low adhesion road needs more attention, and the investigation should consider the coupling of aerodynamics and vehicle dynamics and the combined effect of crosswind and road adhesion. Originality/value Developing a new two-way coupling approach which can capture the complex vehicle structures and the road adhesion with MBD model and the completed fluid filed structure with CFD model. The present study might be the first study considering the coupling of crosswind and low adhesion road. The proposed two-way coupling approach will be useful for researchers who study vehicle crosswind stability.

High speed driving stability of road vehicles under crosswinds: an aerodynamic and vehicle dynamic parametric sensitivity analysis

“…Safety, the perceived level of control and expected comfort in modern cars are reasons for the increased research focus on vehicle handling coupled to unsteady aerodynamics. Many studies available in the literature compare the effects of different aerodynamic features and investigate how to numerically couple aerodynamics and vehicle dynamics in a virtual environment [5][6][7][8]. However, few studies have investigated which aerodynamic and vehicle dynamic design parameters affect the sensitivity to crosswinds the most.…”

“…The guidelines in the ISO 12021:2010 standard include a methodology where a vehicle is driven at 100 km/h into a zone of 20 m/s crosswind, resulting in a relative flow angle of ψ = 35.8 • (Figure 2 shows how the vehicle velocity, v x , and horizontal wind components, w x and w y , affect the relative flow magnitude, V mag , and angle, ψ). The resulting crosswind gust profile has been adopted in several numerical studies of crosswind sensitivity [5][6][7][8]17]. These extreme winds of 20 m/s create high aerodynamic forces and a distinct motion response of the vehicle, useful for measuring differences between vehicles and configurations.…”

“…The inverse simulations could thus enable an approximate solution without using full-scale windtunnels with crosswind excitation abilities. Since such windtunnel facilities are rare, much research has been focused on using computational fluid dynamics (CFD) simulations to model the transient aerodynamic loads during the crosswind gust event [5][6][7][8]14,15,17,25]. The loads can be coupled to vehicle dynamic simulations, to find the vehicle motion response to the gust.…”

Research on transient aerodynamic characteristics of windshield wipers of vehicles

“…In a comprehensive consideration of the flow field around the vehicle and computational efficiency, the computational domain is created as a cuboid embracing the model. And, in view of reasonable results achieved in related references (Tien Phuc et al, 2015;Wang et al, 2017;Yang et al, 2017;Li et al, 2018), the inlet plane is placed at a distance of three times the body lengths ahead of the model, whereas the outlet plane is placed at seven times its length behind the model. The height and width of the computational domain is six times the body height and seven times the body width, respectively, which gives a blockage ratio of 2.64 per cent, and the blockage effect is eliminated according to the experimental studies in the HD-2 Wind Tunnel Laboratory.…”

Coupling analysis of transient aerodynamic and dynamic response of cars in overtaking under crosswinds

“…The real-time dynamic response and aerodynamic forces could be computed by the kinetics model and the aerodynamic model by using the two-way coupling method (Nakasato et al, 2017;Winkler et al, 2016;Wang et al 2020;Zhang et al 2020). At present, this approach has been used to analyse the aerodynamic performance and dynamic response of the vehicle in crosswinds (Huang et al, 2018;Li et al, 2018). The results demonstrated that the influence of the aerodynamic forces on the vehicle motion in the twoway coupling method is greater than that in the one-way coupling method.…”