【作者】 杨振亮；

【导师】 申福林；

【作者基本信息】 长安大学 ， 车辆工程， 2010， 硕士

【摘要】 公路客运作为旅客运输的重要方式,对客车性能有较高要求,而在众多性能中,安全性位居首位。据近年来国内外大量汽车交通事故的统计研究显示,在所有事故中,碰撞事故(正碰、侧碰、追尾和翻滚)占有较大比例,其中追尾碰撞事故虽然在事故总量中的比例仅占8%,但引起的颈部损伤却占30%左右,而这一比例中的5%则是致命性的。在汽车追尾碰撞中,乘员颈部经常会受到挥鞭样损伤,这种损伤将引起多种且持续时间较长的病症(WDA)。颈部损伤的影响因素很多,如座椅结构特征、碰撞时车速、整车质量及乘员个人身体素质等。由于目前各国还没有制定有关汽车追尾碰撞乘员保护法规,只有乘用车正面碰撞乘员保护法规,且仅适用于M1和M2类客车。因此,本论文的主要研究目的是通过对大型客车追尾碰撞的仿真分析,初步了解大型客车在追尾碰撞中影响乘员颈部损伤的主要因素,探讨提高乘员颈部安全性的措施和途径,为今后进一步深入开展大客车追尾碰撞试验和计算机仿真研究,以及制定追尾碰撞的安全法规提供参考。本文首先采用显式有限元分析程序ANSYS/LS-DYNA,参考国内外相关研究资料,建立某6127型客车整车追尾碰撞的有限元仿真模型。模型除整车结构外,还包括HybridⅢ50百分位假人有限元模型、安全带、座椅和移动车模型。随后应用该模型,分析了座椅靠背倾斜角度、头枕到头部距离、乘员坐姿、座椅在客车中的位置、安全带和移动车质量及速度等因素对颈部动力学响应的影响。最后,根据模型输出的主要参数：头枕骨(OC)处的剪切力、弯矩、头部加速度、骨盆处和胸部加速度等,使用颈部损伤准则Nkm和NIC评价颈部损伤风险。仿真结果表明,客车最后排假人颈部Nkm值大于客车中间和前部假人的Nkm值；座椅靠背倾斜角对Nkm值影响较大；随着移动车质量和速度的提高,Nkm值也在增大；头枕位置和乘员坐姿对OC处的剪切力、弯矩和颈部NIC值影响较大；而乘员颈部损伤不仅受座椅参数和移动车特征的影响,还与客车尾部车身吸能结构的吸能特性有关。研究结果还表明,通过以下途径可以减小颈部伤害：在客车尾部结构允许的情况下适当增大座椅靠背倾斜角,并同时保持头枕和头部距离不变；提高车身尾部结构的吸能能力,加强座椅地板骨架的刚度防止座椅向后过度翻转；乘车时缩小头枕和头部的距离或将头靠在头枕上等。更多还原

【Abstract】 Road passenger transport as an important mode of passenger on the bus have high requirements for the bus performance, and the security ranks in many properties.In all incidents, collisions (positive collision, side collision, rear-end and roll) account for a large proportion of a large number of car accidents at home and abroad, according to recent statistical studies have shown that rear-end collisions in which although the proportion of the total in the accident only 8%, but due to neck injury accounts for about 30%, while the proportion of 5% are fatal.In rear-end collision, the crew will often be whiplash neck injury, such damage would lead to multiple and longer duration of illness (WDA).Neck injury in a number of factors, such as the seat structure characteristics, collision speed, quality and passenger vehicle and other personal fitness. As currently developed countries do not make laws and regulations of rear-end collision of the occupant protection, only the passenger frontal impact occupant protection laws and regulations, but only M1 and M2 class passenger. Therefore, the main purpose of this paper is a large bus through the rear-end collision on the simulation analysis, a preliminary understanding of large-scale passenger car occupants in rear-end impact neck injury affecting the main factors of the neck to improve occupant safety measures and means for the future.Firstly, by using explicit finite element analysis program ANSYS/LS-DYNA, a review of relevant research data to establish a 6127-type passenger vehicle rear-end collision of the finite element simulation model. Model includes HybridⅢ50 percentile dummy FE model, seat belts, seat, and mobile vehicle model. Subsequently, using this model, the angle of seat backs, head to headrest distance, the crew sitting position, seat position in the passenger car, seat belts and mobile vehicle quality and speed on dynamic response of the neck.Finally,The main parameters of the model output first occipital (OC) Department of shear force, moment, acceleration of the head and lower neck, with neck injury criterion NIC Nkm and evaluation of the risk of neck injury. Simulation results show that the last row of passenger dummy neck Nkm greater than the middle and front passenger dummy in the Nkm values; seat back angle greater impact on Nkm values; as the quality and speed of moving vehicles increased, Nkm values also increased; head position and the crew sitting on the OC Department of shear force and bending moment greater impact; and not only by the seat occupant neck injury parameters and characteristics of moving vehicles, the rear body with energy absorbing passenger structure of energy absorption characteristics.The results show that the following methods can reduce neck injuries:the tail structure in the bus, where appropriate, to allow increased seat back angle, headrest and head, while maintaining the same distance; to improve body energy absorption tail structure capacity, strengthen the skeleton of the stiffness of the floor seats to prevent the seat back over flip; car when narrowing the distance between headrest and head, or head on the headrest.更多还原