1836圆振动弛张筛动力学参数设计及运动特性分析

发布时间：2018-05-10 05:21

本文选题：圆振动弛张筛 + 动力学模型　；参考：《中国矿业大学》2017年硕士论文

【摘要】：煤炭是我国的基础能源和重要的工业原料,有力支撑了国民经济的发展,煤炭的清洁、高效利用也一直是煤炭分选的重要课题。振动筛分设备是煤炭分选流程的重要组成设备,其工作性能是煤炭能否实现高效分选的关键。但是由于煤层渗水、防尘喷水等原因,导致原煤含有较多外在水分,一般振动筛已经很难胜任分选工作,潮湿细粒煤的直接筛分技术一直没有得到有效地解决。针对以上问题,本文在圆振动筛的基础上,根据动力学原理,提出了圆振动弛张筛,并以筛面弛张原理为基础,设计了圆振动弛张筛的整体结构。基于Lagrange方程,建立了圆振动弛张筛的三自由度动力学模型,并求出解析解,阐明了其进行振动筛分的机理,并以此为根据,选取了相关的动力学参数。利用ADAMS构建圆振动弛张筛的虚拟样机模型,对其进行多体动力学仿真,分析其动力学特性,验证了理论模型及解析计算的正确性。建立圆振动弛张筛的三维模型,对其进行有限元分析,通过模态分析,得出其各阶模态及振型,有效规避了对其平稳工作较为不利的模态,并为谐响应分析奠定基础;进行静力学和谐响应分析,研究圆振动弛张筛的频响特性及等效应力,并据此对其关键部位进行强度校核。鉴于普通弛张筛筛面易损坏的缺点,提出一种新型结构的弹性筛面,并对新型筛面及普通筛面进行有限元对比分析,得出新型筛面无应力集中现象,受力更均衡的结论,为弹性筛面的结构优化及延长使用寿命提供思路。制作圆振动弛张筛的中试样机,通过进行空载工况和带料工况下的动力学实验,对其振动位移信号及动力学参数进行研究。通过对比主筛体和浮动框的水平位移信号,分析其实现弛张原理的相对位移及其空间轨迹等数据;通过对比主筛体上不同测点的竖直位移信号,分析其运动稳定性;通过测试不同激振频率下的主筛体及浮动框水平位移,寻找可以更好实现筛分工作的激振频率。
[Abstract]:Coal is the basic energy and important industrial raw material in our country. It can support the development of national economy. The clean and efficient utilization of coal is always an important task of coal separation. Vibrating screen separation equipment is an important part of coal separation process, and its working performance is the key to the efficient separation of coal. However, due to coal seams seepage and dustproof water injection, the raw coal contains more external water, the general vibrating screen has been very difficult to do the sorting work, and the direct screening technology of wet fine coal has not been effectively solved. In view of the above problems, based on the circular vibrating screen, according to the dynamic principle, the circular vibration relaxation screen is put forward, and the integral structure of the circular vibration relaxation screen is designed on the basis of the screen surface relaxation principle. Based on the Lagrange equation, a dynamic model of three degrees of freedom for a circular vibrating relaxation screen is established, an analytical solution is obtained, and the mechanism of carrying out the vibrating screen is clarified. Based on this, the relevant dynamic parameters are selected. The virtual prototype model of circular vibration relaxation screen is constructed by using ADAMS. The multi-body dynamics simulation is carried out and its dynamic characteristics are analyzed. The correctness of the theoretical model and analytical calculation is verified. The three-dimensional model of circular vibration relaxation screen is established, and the finite element analysis is carried out. Through modal analysis, the modes and modes of each order are obtained, which effectively avoid the more unfavorable modes to its smooth operation, and lay the foundation for harmonic response analysis. The frequency response characteristics and equivalent stress of circular vibration relaxation screen were studied by statically harmonious response analysis, and the strength of the key parts was checked accordingly. In view of the defect that the common relaxation screen surface is easy to be damaged, a new type of elastic screen surface is proposed, and the finite element contrast analysis between the new type screen surface and the ordinary screen surface is carried out, and the conclusion is drawn that the new type screen surface has no stress concentration phenomenon and the force is more balanced. It provides ideas for structural optimization and extension of service life of elastic sieve surface. The vibration displacement signal and dynamic parameters of circular vibrating relaxation screen were studied by dynamic experiments under no-load and strip conditions. By comparing the horizontal displacement signals of the main screen body and the floating frame, the relative displacement and the space track of the relaxation principle are analyzed, the vertical displacement signals of different measuring points on the main screen body are compared, and its motion stability is analyzed. By measuring the horizontal displacement of the main sieve and the floating frame at different exciting frequencies, the exciting frequency of sieving can be better realized.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD452

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