摘要
铰接式车辆车体结构复杂,需要对车体的固有特性进行分析,防止在运行中不同激励作用下出现共振现象。针对整车在正常行驶工况下的受力情况进行分析,获取车体结构振动基本方程;基于有限单元法建立车架有限元分析模型,分别获得前车体、后车体的前八阶固有频率和振型;分析路面激励和发动机激励对车体动态特性的影响,对车体的动态特性进行评价;基于车体激励试验台,分析路面激励、发动机激励等对车体振动的影响,以检验设计的可靠性。结果可知:前车体固有振型主要是1个或几个部分振动为主的局部振动;前车体的前8阶弹性模态频率分布在(30~66)Hz范围内;后车体的前8阶弹性模态频率分布在(14~51)Hz范围内;前车体的一阶频率为30.85Hz,后车体的一阶频率为14.15Hz,高于路面的激励频率范围;前车体的(1~4)阶固有频率低于发动机怠速时的频率,(5~8)阶高于发动机的怠速时的频率(40Hz),不会引起共振;质心位置振动变化在三种作用形式下均未出现明显的激振情况。在激励作用下,振动幅度较输入激励略低,主要由于车辆减震器的作用,吸收了部分激励。表明设计是合理,分析过程可以作为此类研究的参考。
The structure of the articulated vehicle frame is complex,and it is necessary to analyze the inherent characteristics of the frame to prevent resonance phenomenon under different excitations during operation. According to the analysis of the force of the whole vehicle under normal driving conditions,the basic equation of the structural vibration of the vehicle body was obtained. The finite element analysis model of the frame was established based on the finite element method and the first eight intrinsic bodies of the front and rear frame were obtained respectively. The influence of road excitation and engine excitation on the dynamic characteristics of the vehicle frame was analyzed,and the dynamic characteristics of the vehicle frame were evaluated. Based on the vehicle frame excitation test bench,the effects of road surface excitation and engine excitation on the vibration of the vehicle body were analyzed to verify the reliability of the design. The results show that the natural vibration mode of the front body is mainly local vibration with one or several partial vibrations;the first 8 th elastic mode frequency distribution of the front frame is in the range of(30~66)Hz. The first 8 th elastic mode frequency distribution of the rear frame is in the range of 14 to 51 Hz. The first-order frequency of the front frame is 30.85 Hz,and the first-order frequency of the rear frame is 14.15 Hz,which is higher than the excitation frequency range of the road surface. The 1 st to 4 th order natural frequencies of the front frame are lower than the engine idle frequency. The frequency of(5~8)steps is higher than the idling speed of the engine(40 Hz),which does not cause resonance. The vibration of the centroid position did not show obvious excitation under the three modes of action. Under the action of excitation,the vibration amplitude is slightly lower than the input excitation,mainly due to the action of the vehicle shock absorber,which absorbs part of the excitation. It indicates that the design is reasonable and the analysis process can be used as a reference for such research.
作者
孙静霞
冯益增
王永莉
SUN Jing-xia;FENG Yi-zeng;WANG Yong-li(Vehicle Engineering Department,Shandong Transport Vocational College,Shandong Weifang 261206,China)
出处
《机械设计与制造》
北大核心
2021年第12期145-149,共5页
Machinery Design & Manufacture
基金
山东省职业教育教学改革研究项目(2019655、鲁教职字[2016]14号)。
关键词
铰接车
车体
固有特性
激励
共振
模态
Articulated Vehicle
Frame
Inherent Characteristics
Excitation
Resonance
Modal
