Research On Human Ear Pressure Comfort During Door Closure Of Passenger Car

In recent years, people’s life has been greatly promoted with the rapid development ofChinese economy, so the ride comfort is becoming more and more important to the customerswhen they buy vehicles. Therefore, producing a car with good ride comfort is particularlyimportant for the manufacturer. Currently, some passengers feel uncomfortable and dizzywhen they close the door. In order to improve the ride comfort, it is necessary to research onthis phenomenon and offer corresponding solutions.When the door is being closed, pressure will be suddenly generated in the cab. Suddenincreased pressure will act on the eardrum, resulting in the deformation of tympanic membranewhich would make the occupant feel discomfort. Given the sudden increased pressuregenerated in the cab when the door is being closed would affect passenger’s ride comfort andthe compressed air in the cab would develop resistance to the closing of the door, it ismeaningful to research the factors that affect the maximum pressure when the door is beingclosed and analyze for the flow field of the cab.Overset mesh in software SC/TETRA was used in this paper. The door closing processwas numerical simulated using overset mesh to research the factors that affecting the value ofthe pressure at the passenger’s ears. In this paper, the research is divided into three parts. Thefirst part studies the effect of door’s angular velocity on the pressure at the passenger’s ears.The second part studies the effect of the leakage area of car body on the pressure at thepassenger’s ears. The third part studies the effect of the different location of leak on thepressure at the passenger’s ears and this part was based on the first part. In addition, analysisof the flow field structure in the cab were included in these three parts.In the first part, door of five different angular velocity was simulated. The five angularvelocity are2rad/s,4rad/s,6rad/s,8rad/s and10rad/s. Simulation results showed that theangular velocity of door had a great impact on the pressure at the ear and with the increasedof door’s angular velocity, the pressure at the ear increased almost linearly. In the second part, leakage area of80cm2,100cm2,120cm2,140cm2and160cm2was simulated at the conditionof2rad/s and4rad/s. Simulation results showed that with the increase of the leakage area, thepressure value at the ear decreased linearly, but it decreased little. In the third part, fourdifferent location of the leak was established based on the flow field structure informationfrom the simulation of the first part. The total leakage area of the leak was140cm2in the fourdifferent schemes. Door of2rad/s was simulated in the three part. Simulation results showedthe location of leak had a certain influence on the pressure at the ear, but the effect was notvery obvious. Change the location of leak can reduce the pressure at the eras. The pressuredecreased when the leak was in the right rear corner of the cab (trunk department) and the rightfront corner (instrument panel).The flow structure was also analyzed in this paper. By analyzing the flow we can find thegas around the door would be involved in the cab, and flow clockwise in the cab at thebeginning of door closure, and then the gas would flow towards different directions dependingon the door’s angular velocity and the location of leak. In conclusion, the location of leak hada much greater impact on the flow field while the closing-door angular velocity did little. Inaddition, the leakage area had little effect on the flow structure.