Structure Optimization Of The Sliding Door Retention Components For Commercial Vehicle Based On GB15086-2013

With the increase of traffic accidents,more and more attention has been paid to the safety of vehicles.The lateral strength of car door,as an important part of the car body,is directly related to the safety of the passengers.On September 18,2013,the National Standards Committee of China issued Motor vehicles’ door locks and retention components performance requirements and test methods,which were more detailed in the sliding door retention components tests and evaluation criteria compared with the2006 version.The traditional test methods had the characteristics of long design cycle,high risks and high costs.Moreover,the sliding door retention parts tended to gain more mass in order to pass regulations,which reduced its market competitiveness.Therefore,it is of great significance to analyze the regulation and optimize structure about the sliding door retention components.For a commercial vehicle’s sliding door can not meet the requirements of the present regulations,finite element simulations and experimental verifications were carried out to analyze the regulation and optimize the sliding door retention parts in this paper.The main researches and results are as follow:1.The car body mesh models were established on HyperMesh and were endowed the real mechanical behavior and properties of materials.After setting the connections in accordance with the actual locations of welds,bolts,and creating loads and constraints based on regulatory tests,the finite element models were established for analyzing the sliding door retention components.2.The results of simulation by LS-DYNA were in good agreement with the experimental results,which proved the accuracy of the finite element models.After improving the two weak regions of mid-rail and latch on basis of simulation results,the simulation results met the regulation requirements for the track and the slide combination did not separate from the doorframe,the displacement of loading plate was less than 300 mm and the maximum separation distance between the doorframe and the door was 93.3 mm,less than 100 mm.But the vehicle mass increased by 2.8 kg.3.Based on the sensitivity analysis theory,six reinforcing parts around the sliding door were chosen as the analysis object to carry out the sensitivity analysis.Taking the total weight of the components as the objective function,the maximum separation distance between the exterior edge of the doorframe and the door interior as theconstraint function,the sensitivity of maximum separation distance to component thickness was obtained by LS-DYNA calculation.After the part thickness was optimized on the basis of the relative sensitivity,the maximum separation distance between the doorframe and the door only increased 4 mm comparing with that before optimizing and still met the regulatory requirements,and the weight loss was about 2.2kg,which were verified by load tests at last.4.By analyzing the influence of the position changes of the middle guide rail,hook and latch on sliding door retention components tests,the conclusions can be obtained as follow: When the positions of the middle guide rail and the latch were unchanged,the distance between the upper of the door interior and the exterior edge of the doorframe gradually increased,however the distance between the lower of the door interior and the exterior edge of the doorframe gradually reduced,with the drop of the hook position.When the hook was located at the position of 72% body height or more,the sliding door can not meet the regulatory requirements for the upper guide wheel always escaped from the rail.As the latch position was higher than the middle guide rail,the upper guide wheel was easily disengaged from the rail.When the middle guide rail was located at 48%,the latch and the hook were located at 64% body height,these connection locations were the optimal for the separation distance between the doorframe and the door was the minimum.