Study On Vehicle Window Water Management Based On Particle Tracking Method And Liquid Film Theory

The ability of vehicles to travel safely for long periods of time in rainy weather or on waterways has been listed as one of the important research projects in automotive aerodynamics.At present,the research on external water management of car body can be divided into three categories according to the water source,namely,rainfall,self-splashing water and external vehicle splashing water.In the aspect of rainfall,the author mainly studies the safety effects of the phenomena such as blurred vision or surface pollution caused by the rain falling on the outer surface of the vehicle when the vehicle is driving in rainy weather.Self-splashing is mainly studied when the vehicle moves to the water area,the water flow pollution on the body surface caused by the impact of the wheels and the rotation of the wheels.External vehicle splashing is to study the impact of polluted water flow generated by other vehicles splashing on their own body.Since most of the view of the vehicle's front window can be solved by front wiper drive,this paper focuses on the analysis of the relatively important view of the driver's front window.The view of the side window of a vehicle has a very important effect on the safety of driving.On the one hand,the view of the side window determines whether the driver can observe the rearview mirror clearly.On the other hand,when the vehicle is steering,it needs to have a good enough view from the side window.In previous studies,the researchers analyzed the water flow distribution of the vehicle surface and the motion state of particles around the vehicle body when the vehicle was running in the rain,but they did not change the geometric shape of the body surface to improve the water adhesion.In this paper,STAR CCM+ was used to simulate the water management of an SUV.First of all,the transient simulation calculation of the basic model is carried out.The rain water adhesion state in 5s with wiper drive and without wiper is calculated respectively.The flow and distribution of liquid film on the side window ofthe basic model are obtained.Combined with some characteristics of the body's outflow field structure,the paper analyzes the source of the liquid film on the side window,and makes a summary for changing the external shape.Some modifications were made to the relative positions of column A and rearview mirror for the main source of water adhesion.The simulation calculation of the modified design model is the same as that of the basic model.The volume and thickness distribution of the window film were compared to compare the difference in water management performance between the modification scheme and the base model.At the same time,according to the center of the eye ellipse,a method for evaluating the visual field of the driver's side window is established.A more detailed quantitative analysis was carried out on the changes of the water adhesion state of the side window produced by the modification scheme.