| Biomass densification technology supply raw materials for other biomass energy utilization technologies. As an important renewable energy, efficient development and utilization of biomass energy can not only contribute to alleviate energy shortage status all over the world, but also improve the ecological environment. Countries around the world attach great importance to developing biomass densification technology, but there are still some development bottlenecks, such as high energy consumption, low productive capacity, wide ranging product quality, short lifetime of key components, excessive vibration and noise. These problems give directions to development trend of biomass densification technology.The characteristics of energy consumption and the destructional forms of the equipment are analyzed in this paper, come to a conclusion that the ring die and spindle parts are the most important components of biomass densification equipment. Biomass densification process is numerical simulated by using the theoretical knowledge of plasto-elasticity, contact mechanics and viscoelasticity theory. The deformation principles and rheologic laws are revealed during briquette process, the stress distribution of ring die is obtained, and the regularity for change of briquette pressure is also obtained. The analysis results show that material flow velocity on axis part is faster than other parts. The lowest flow velocity appears on edges of briquettes, the Von-Mises stress reached the highest value correspondingly. There has a sharp decline of stress in briquette after flowing out from the die hole, but residual stress still exist. This is the first time to study the phenomenon that ring die material flaking off and briquette ripping on edges by analyzing densification mechanism and the stress-strain distribution. An improved scheme is presented and compared with the customary model. The study comes to a conclusion that the improved scheme can reduce the stress value on briquette edges effectively, and make stress distribution more reasonable.Spindle part is at the risk of fatigue failure, the dynamic response characteristics are studied by establishment dynamic equation and analysis mass matrix. First of all, study on natural frequency and the mode of spindle parts are carried out. The critical speed of spindle is 3665.52r/min, analysis showed that the work frequency is far away from the critical speed, the structure can avoid the resonance region effectively. Secondly, the spindle part which support the load, varies according to simple harmonic regular is analyzed by using vibration mode superposition method, the dynamic response characteristics is gotten. The largest response to displacement is 1.25×10-3m, and the largest response to stress is \56MPa under working frequency. There is a compared study about effectiveness of spindle support span to structure dynamic response characteristics. By decrease the support span from 480mm to 430mm, the maximum stress and the maximum displacement are come to an upward trend in both, stability of structure is decreased.This paper carried out quantitative analysis systematically on mechanical properties and vibration response characteristics of briquetting equipment based on ANSYS software. A large number of experiments were done to study the biomass densification pressure and the relation between stress-strain in briquette process. In this paper, these experimental research data was analyzed and verified based on theoretical research foundation. The steady-state response characteristics of briquetting equipment is mastered in this paper, it also laid a foundation for optimizing structure design and analyzing reliability of briquetting equipment.
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