某型林用消防车振动特性研究
发布时间：2019-05-30 09:12
【摘要】：结合我国林区防火需求和消防车研究现状,本文以一款由越野车底盘改装而成的小型多功能消防车为研究对象,运用理论分析、试验研究和计算机仿真相结合的方法,对样车的振动特性进行了系统的研究。考虑样车实际作业情况,振动平顺性的研究选择空载和满载两种工况,根据GB/T4970,选取B、D路面等级下的三种常用车速来进行室内道路模拟试验和Matlab仿真；并依据GB/T7031采用总加权加速度均方根值法进行评价。经过仿真和试验分析可知：消防车振动响应值较大,这主要是由于路况条件、载荷和车速等因素造成的,且由于Matlab仿真时建立的消防车数学模型是个理想的模型,忽略了发动机激励和流体运动的影响,所得平顺性结果优于试验结果,误差值在5%左右。此外,通过对悬架固有频率和阻尼比进行重新匹配实现了对消防车模型的优化仿真,优化后的加速度有效值改进了8%左右。消防车改装后主要用于运水,因此在本研究中,将载荷对整车振动的影响作了深入的探究。首先利用Hypermesh和Nastran分析了消防车水罐在空载、50%充水、75%充水、100%充水4种工况下的流固耦合模态,得出了各充水工况下前三阶振动固有频率值,同时得出响应的振动模态,分析可知：罐体随充水量的增加振动明显,且振动无突变属于正常振动。另通过D级路面车速20km/h下四种充水工况下的试验研究,得出了响应的振动响应值,并利用频域分析细化了流固耦合对整车振动的作用效果。此外,利用试验研究分析了发动机激励对整车振动的影响,通过测量怠速(850rpm)、1500rpm、2500rpm和最大转速(3500rpm)下的6个测点的加速度时间曲线和加速度功率谱曲线,对结果进行了时域和频域分析。得出发动机转速越快对整车振动影响越大,主要体现在对座椅垂向、横向和前轴的影响。通过本文研究,得出了样车振动情况受路面条件、车速、载荷(流固耦合)及发动机激励等因素的影响,整车整体振动响应值较大,即振动明显。基于文章研究,建议对悬架、水罐隔波板、发动机悬置系统进行优化,并在使用时控制车速,同时避免半载工况运行。
[Abstract]:According to the demand of forest fire prevention in China and the present situation of fire engine research, this paper takes a small multifunctional fire truck modified from off-road vehicle chassis as the research object, using the method of theoretical analysis, experimental research and computer simulation. The vibration characteristics of the sample car are studied systematically. Considering the actual operation situation of the sample car, the vibration ride comfort research selects two kinds of working conditions: no load and full load. According to GB/T4970, three kinds of commonly used vehicle speeds under B, D road grade are selected to carry out indoor road simulation test and Matlab simulation. According to GB/T7031, the total weighted acceleration root mean square method is used for evaluation. Through simulation and experimental analysis, it can be seen that the vibration response of fire engine is large, which is mainly caused by road condition, load and speed, and because the mathematical model of fire engine established in Matlab simulation is an ideal model. The effects of engine excitation and fluid motion are ignored, and the ride comfort results are better than the test results, and the error value is about 5%. In addition, the optimization simulation of the fire engine model is realized by matching the natural frequency and damping ratio of the suspension, and the effective value of the optimized acceleration is improved by about 8%. After refitting the fire engine, it is mainly used to transport water, so in this study, the influence of load on the vibration of the whole vehicle is deeply studied. Firstly, the fluid-solid coupling modes of fire truck water tank under four working conditions of no load, 50% water filling, 75% water filling and 100% water filling are analyzed by using Hypermesh and Nastran, and the natural frequency values of the first three vibration under each water filling condition are obtained. At the same time, the vibration mode of the response is obtained. The analysis shows that the vibration of the tank is obvious with the increase of water filling, and the vibration does not change to the normal vibration. In addition, through the experimental study under four kinds of water filling conditions under D grade pavement speed 20km/h, the vibration response value of the response is obtained, and the effect of fluid-solid coupling on the vibration of the whole vehicle is refined by frequency domain analysis. In addition, the influence of engine excitation on the vibration of the whole vehicle is studied and analyzed by experiments. The acceleration time curves and acceleration power spectrum curves of six measuring points at idle speed (850rpm), 1500rpm, 2500rpm and maximum speed (3500rpm) are measured. The results are analyzed in time domain and frequency domain. It is concluded that the faster the engine speed, the greater the influence on the vibration of the whole vehicle, which is mainly reflected in the vertical, transverse and front axle of the seat. Through the study of this paper, it is concluded that the vibration of the sample vehicle is affected by road conditions, speed, load (fluid-solid coupling) and engine excitation, and the overall vibration response of the vehicle is large, that is to say, the vibration is obvious. Based on the research of this paper, it is suggested that the suspension, water tank separator and engine mounting system should be optimized, and the speed should be controlled when in use, and the operation under half load condition should be avoided at the same time.
【学位授予单位】：北京林业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U469.68
本文编号：2488721
[Abstract]:According to the demand of forest fire prevention in China and the present situation of fire engine research, this paper takes a small multifunctional fire truck modified from off-road vehicle chassis as the research object, using the method of theoretical analysis, experimental research and computer simulation. The vibration characteristics of the sample car are studied systematically. Considering the actual operation situation of the sample car, the vibration ride comfort research selects two kinds of working conditions: no load and full load. According to GB/T4970, three kinds of commonly used vehicle speeds under B, D road grade are selected to carry out indoor road simulation test and Matlab simulation. According to GB/T7031, the total weighted acceleration root mean square method is used for evaluation. Through simulation and experimental analysis, it can be seen that the vibration response of fire engine is large, which is mainly caused by road condition, load and speed, and because the mathematical model of fire engine established in Matlab simulation is an ideal model. The effects of engine excitation and fluid motion are ignored, and the ride comfort results are better than the test results, and the error value is about 5%. In addition, the optimization simulation of the fire engine model is realized by matching the natural frequency and damping ratio of the suspension, and the effective value of the optimized acceleration is improved by about 8%. After refitting the fire engine, it is mainly used to transport water, so in this study, the influence of load on the vibration of the whole vehicle is deeply studied. Firstly, the fluid-solid coupling modes of fire truck water tank under four working conditions of no load, 50% water filling, 75% water filling and 100% water filling are analyzed by using Hypermesh and Nastran, and the natural frequency values of the first three vibration under each water filling condition are obtained. At the same time, the vibration mode of the response is obtained. The analysis shows that the vibration of the tank is obvious with the increase of water filling, and the vibration does not change to the normal vibration. In addition, through the experimental study under four kinds of water filling conditions under D grade pavement speed 20km/h, the vibration response value of the response is obtained, and the effect of fluid-solid coupling on the vibration of the whole vehicle is refined by frequency domain analysis. In addition, the influence of engine excitation on the vibration of the whole vehicle is studied and analyzed by experiments. The acceleration time curves and acceleration power spectrum curves of six measuring points at idle speed (850rpm), 1500rpm, 2500rpm and maximum speed (3500rpm) are measured. The results are analyzed in time domain and frequency domain. It is concluded that the faster the engine speed, the greater the influence on the vibration of the whole vehicle, which is mainly reflected in the vertical, transverse and front axle of the seat. Through the study of this paper, it is concluded that the vibration of the sample vehicle is affected by road conditions, speed, load (fluid-solid coupling) and engine excitation, and the overall vibration response of the vehicle is large, that is to say, the vibration is obvious. Based on the research of this paper, it is suggested that the suspension, water tank separator and engine mounting system should be optimized, and the speed should be controlled when in use, and the operation under half load condition should be avoided at the same time.
【学位授予单位】：北京林业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U469.68
【相似文献】
相关期刊论文 前10条
1 马书义;;降低两轮轻便踏板摩托车整车振动对策的研究[J];装备制造技术;2012年10期
2 张志弘;何玉林;杜静;孙学军;;摩托车整车振动性能匹配优化设计技术的研究[J];中国机械工程;2005年23期
3 张立军,符朝兴,王岩松;车辆整车振动模型自由度的模糊选择[J];公路交通科技;2003年01期
4 陈少锋;陈劭;于文华;;整车振动平顺性的研究发展动态[J];科技创新导报;2012年16期
5 符朝兴 ,张立军;汽车整车振动模型自由度的模糊分析与选择[J];现代机械;2002年02期
6 朴英花;马天飞;;利用刚弹耦合模型进行整车振动的仿真计算[J];汽车技术;2006年11期
7 曲守平,杨小波,胡子正;用ERA法建立计及传动系扭振的整车振动模型[J];汽车技术;1994年12期
8 李怡雪;;无感振动 完美极速——隆鑫极舒系列发动机强势来袭[J];摩托车信息;2014年03期
9 毛竹君;周建刚;徐贤;陈伟;黄值仪;;轮胎模态分析在整车振动问题诊断的应用[J];汽车科技;2014年04期
10 陈永新,张作洋,戴茂方;SUV整车振动噪声的试验研究[J];汽车技术;2005年07期
相关会议论文 前2条
1 孙恬恬;马忠民;刘宏江;方华;周宏伟;;某越野车整车振动噪声的试验研究[A];2013中国汽车工程学会年会论文集[C];2013年
2 杭磊;黄锦洋;;微型车振动和噪音的研究与改进[A];自主创新、学术交流——第十届河南省汽车工程科学技术研讨会论文集[C];2013年
相关硕士学位论文 前6条
1 刘新颖;某型林用消防车振动特性研究[D];北京林业大学;2016年
2 李娟;前置后驱动汽车的整车振动耦合研究[D];吉林大学;2012年
3 余烽;5000公斤全地域机动平台整车振动噪声测试与分析[D];重庆大学;2008年
4 高晓萍;运输车整车振动的综合分析[D];山东科技大学;2006年
5 陈浩;整车振动环境下考虑橡胶减振支撑圈的传动轴振动分析[D];南京航空航天大学;2014年
6 刘从臻;双轴车辆整车振动特性试验研究[D];甘肃农业大学;2006年
，本文编号：2488721
本文链接：https://www.wllwen.com/kejilunwen/qiche/2488721.html
