弧形弛张筛筛面动力学分析与设计

发布时间：2018-05-09 17:00

本文选题：弧形弛张筛 + 动力学　；参考：《太原理工大学》2015年硕士论文

【摘要】：弛张筛是筛分潮湿、粘性大等难筛细粒物料的重要设备，具有筛分效率高、筛孔不易堵塞、噪声低等优点，在近几十年获得了很大的发展。弛张筛的筛面结构与振动特性直接影响筛面上物料的运动和透筛，能决定弛张筛筛分效率的高低。因此对弛张筛筛面进行的动力学分析与结构设计对于提高弛张筛的筛分效率具有重要的理论意义。本文首先阐述弛张筛、弧形筛面设计和筛分工作等原理，建立弛张筛动力学模型，推导得到其振动方程和振幅表达式。分析发现，，弛张筛的简谐振动特点使得其位移振幅对弛张筛振动特性影响很大。然后分析影响振幅的各个参数，并利用循环求解法对各个参数非线性取值。最后利用ADAMS计算验证弛张筛前面分析的动力学特性。通过研究弛张筛筛面的筛板传统变形数学模型，结合筛面运动的多重运动特性：浮动筛框的大幅运动、筛箱的小幅运动和聚氨酯筛板的大挠度非线性变形运动特点，确定使用悬链线理论模型模拟筛板变形。然后通过分析悬链线的理论推导出筛板变形的挠度曲线表达式，利用MATLAB计算得到了筛板变形结果，再分别与实验测量结果和Workbench仿真结果比较发现误差都很小，验证了悬链线模型的可行性。最后利用悬链线理论推导弧形筛面倾斜筛板的振动特性，以及各主要参数对筛板振动最大速度和加速度的影响。结合筛面振动情况复杂的情况，分析颗粒在筛面上的受力和颗粒的定常运动，推导颗粒运动与筛面倾角和斜抛角的关系。然后分析颗粒在筛面上的理论透筛概率与筛面角度参数的关系，再利用概率论设计筛分效率的计算和表达方法，并推导出满足理论筛分效率所需的弧形筛面长度。最后对筛面的曲线函数作了推导和作图。从而达到弧形弛张筛筛面动力学分析和形状参数设计的目的。
[Abstract]:Relaxation screen is an important equipment for screening fine materials such as moisture and viscosity. It has many advantages such as high screening efficiency, easy blocking of sieve holes, low noise and so on. It has gained great development in recent decades. The structure and vibration characteristics of the relaxation screen directly affect the movement and screening of the material on the screen surface, and can determine the screening efficiency of the relaxation screen. Therefore, the dynamic analysis and structural design of the relaxation screen surface are of great theoretical significance for improving the screening efficiency of the relaxation screen. In this paper, the principles of relaxation screen, curved screen surface design and screening work are introduced, the dynamic model of relaxation screen is established, and the vibration equation and amplitude expression are derived. It is found that the simple harmonic vibration of the relaxation screen makes its displacement amplitude have a great influence on the vibration characteristics of the relaxation screen. Then the parameters affecting the amplitude are analyzed, and the nonlinear values of the parameters are determined by the cyclic solution method. Finally, the dynamic characteristics of the front analysis of the relaxation screen are verified by ADAMS calculation. Through the study of the traditional deformation mathematical model of the relaxation sieve surface, combined with the multiple motion characteristics of the sieve surface motion: the large motion of the floating screen frame, the small motion of the screen box and the characteristics of the large deflection nonlinear deformation of the polyurethane sieve plate. A catenary theoretical model is used to simulate the deformation of sieve plate. Then the deflection curve expression of sieve plate deformation is deduced by analyzing catenary theory, and the result of sieve plate deformation is obtained by MATLAB calculation. Compared with the experimental results and Workbench simulation results, the error is very small. The feasibility of catenary model is verified. Finally, the vibration characteristics of inclined sieve plate with curved sieve surface are deduced by catenary theory, and the influence of main parameters on the maximum velocity and acceleration of vibration of sieve plate is obtained. Combined with the complex vibration of the sieve surface, the force acting on the sieve surface and the steady motion of the particle are analyzed, and the relationship between the particle motion and the inclined angle and oblique angle of the sieve surface is deduced. Then, the relationship between the theoretical screening probability and the angle parameters of the sieve surface is analyzed, and then the calculation and expression method of the sieve efficiency is designed by using probability theory, and the length of the arc screen surface which meets the theoretical screening efficiency is deduced. Finally, the curve function of the screen surface is deduced and drawn. In order to achieve the purpose of dynamic analysis and shape parameter design of curved relaxation screen.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD452

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