Font Size: a A A

Investigation On The Dynamics Of Rigid-Granular Coupling In Eccentric Vibration Mill With Double Rigid Bodies

Posted on:2012-08-31Degree:MasterType:Thesis
Country:ChinaCandidate:J HanFull Text:PDF
GTID:2211330362952933Subject:Mechanical engineering
Abstract/Summary:PDF Full Text Request
The vibration mill is one of the most widely used fine grinding machinery in the powder industry. The vibration energy in the conventional vibration mill is transferred from the wall of the tube to the grinding media contacted with it by collision, and then inwards layer by layer through the media. At the same time, the materials trapped between them are comminuted to smaller size by the impact. Force caused by the collisions. As a sequence of energy scattering, low energy zones develop in center of excited fillings, which leads to a very wide grain-size distribution and low the efficiency, and seriously limited the development of large-scale. The vibration mill double rigid-body is a new design in light of these problems. The theoretical and experimental study, and the latest improvement of double rigid-bodies vibration mill have been carried out in this dissertation.First of all,the dynamic model and analysis have been done for the characteristics of double rigid-bodies vibration mill. Lagrange equation, by six degrees of freedom dynamic equations of the two-rigid body vibration mill system, application Mple calculation software calculated the center of rigid body and the trajectory of each point, the absolute displacement, relative displacement and velocity, found on the mill tube than outside the center of mass point and the center of rigid body trajectories are elliptical, but the center of the vibration intensity was significantly greater than the rigid body vibration intensity, and they always have a phase difference, the real two-way transfer of energy. Application Virtual Prototype Technology modeled of rigid bodies vibrating mill, obtained system the force of bearings and the spring force of the system through the simulation, provide the basis for power calculation of the vibration mill.Second, the dynamic model and analysis have been done for the grinding medium of the double rigid-bodies vibration mill. The grinding of vibration mill is through collision between the tube and the medium. Based on discrete element method, established the dynamic model, through the simulation researched on the movement of medium and the coupling dynamic of rigid-bodies and bulks, and studied the different of the energy distribution with the central rigid body form the energy point, in order to understand the movement of grinding medium and the coupling dynamic rigid-bodies and bulks and provide a theoretical basis for improving the grinding efficiency. It confirmed the central rigid body played a positive role in increasing energy in the tube and distributing the energy.Finally, with theoretical analysis and experimental researching on the central rigid body, optimized the structure of vibration mill, and confirmed the advantages of the program through grinding experiments. Further research and issues put forward. This work on the development of vibration mill has some significance.
Keywords/Search Tags:Double rigid-bodies vibration mill, low-energy zone, central body, coupling dynamic of rigid-bodies and bulks, dynamic of bulks, dynamic of rigid-bodies, discrete element method
PDF Full Text Request
Related items