Research On Simulation Technology Of Ear Pressure During Door Closure Of A Model

With the development of our society,people’s living standards have been significantly improved.Despite the widespread popularity of private cars,passengers’ requirements for private cars are no longer satisfied with safety and convenience,but more attention is paid to ride comfort.In recent years,it has been found that there is a large air pressure during the door closure process in some cars,causing obvious dizziness and pressure ears to the driver and passengers,which seriously affects the ride comfort of the vehicle.The ear presure that occurs when the car is closed is caused by the air resistance effect during the door closure process,in this process,the external air flow is pressed into the crew cabin by the door,however,the pressure in the car can be increased owing to the insufficient pressure relief,and the pressure in the crew cabin can reach the peak at the moment the door is closed,the sudden change in the pressure in the crew cabin and the magnitude of the peak pressure are the main reasons for the discomfort of the passenger.Therefore,It is particularly important to study the pressure changes and flow characteristics of the human ear during the door closure process,so as to provide a reference for solving the ear pressure of door closure.In this thesis,in order to solve the problem of ear pressure when the door is closed in some cars,the position of the left ear of the driver and the left ear of the right rear occupant were monitored for pressure measurement,and research on the simulation method of ear pressure when the door is closing was carried out based on a production model.First of all,through the analysis of the past simulation methods of ear pressure when the door is closing,the existing simulation method was improved for the velocity input of the simulation calculation and seal structure.The improved calculation model took the collected transient velocity of the door during the test as the simulation calculation input,realized the rotation of the door through the overset mesh technology,and used the Overset Mesh Zero Gap function of the STAR-CCM+software to simulate the compression of the sealing strip when closing the door.The comparison of the calculation results before and after the improvement showed that the calculation results of different speed inputs exhibited difference convergence and the calculation results without considering the sealing strip structure were relatively low.Then,multiple comparisons between simulation calculations and experimental test results showed that the calculation result using the actual-measured door closure speed as input was closer to the true value,and the error between the two monitoring points and the measured pressure was 10.6% and 15.9%,and after considering the seal structure,the errors of the simulation calculation were 4.1% and 9.3% respectively,and the simulation method was improved,and the accuracy was above 90%.Finally,in order to further verify the engineering practicability of the simulation method,based on a vehicle model under study,the door closure pressure simulation calculation was studied and a series of optimization schemes were proposed.Studies have shown that evenly arranging the airflow channels of the entire vehicle and appropriately increasing the area of the airflow hole can effectively reduce the peak pressure when closing the door,and improve the problem of ear pressure.The ear pressure of the monitoring point of the vehicle model was optimized to be below 170 Pa to meet the requirements of human ear comfort by comprehensively adopting various optimization measures.