【作者】 德雪红；

【导师】 俞国胜；

【作者基本信息】 北京林业大学 ， 机械设计及理论， 2014， 博士

【摘要】 在生物质物料成型领域,尤其是环模成型机成型物料过程中,由于摩擦磨损而产生的高能耗、高成本,大大削弱了环模机的普及率,使环模市场接受能力一直不高。因此控制摩擦、减少磨损、改善节能性能以及合理发挥材料的潜能等的摩擦磨损研究在工程中具有重要意义。本文所作的研究不仅为新型柱塞式生物质环模成型设备关键参数的选择提供理论依据,以《“十二五”国家科技支撑计划项目(2012BAD30B0205)》为支撑,作为轻型可移动式环模生物质成型燃料制造关键技术研究的一部分,并对新型柱塞式生物质环模成型机的设计和制造提供重要理论与参考依据。本文运用分形非线性理论为基础理论来研究生物质成型物料-环模凹模的摩擦磨损过程的动力学行为,揭示磨损过程中的行为规律,同时对环模凹模的磨损总量进行预测,研究内容主要如下：(1)分析柱塞式生物质环模成型机的成型环模失效原因及形式,对其进行受力及失效分析,确定磨损是环模失效的主要原因。(2)利用分形理论,结合环模凹模粗糙表面分形特性,导出环模凹模与物料接触面积的计算公式,采用分形方法中的W-M函数法表征环模凹模和成型物料粗糙表面曲线,利用MATLAB计算功能及Solidworks的建模功能,建立分形表面接触几何模型及环模凹模-成型物料表面接触有限元模型。(3)基于分形理论及粗糙分形表面接触模型,建立考虑成型物料及环模凹模物理特性的环模凹模内壁磨损预测方程,预测验证程序的正确性的同时探讨环模凹模磨损预测模型的典型参数与平均磨损率的关系,同时分析不同种类的物料及环模材质条件下环模凹模总磨损量随磨损时间的变化规律,并实现环模凹模随磨损时间的总磨损量的预测,为柱塞式环模设计提供理论依据。(4)对环模凹模磨损预测程度模型进行试验验证。通过两种类型的环模及不同规格凹模进行磨损试验测量,验证环模凹模磨损预测程度的正确性。(5)对环模凹模的摩擦热与结构进行耦合分析,确定在不同时刻环模凹模温度场及应力场分布情况,分析在不同的成型物料及不同的环模材质条件下环模凹模由于摩擦生热而引起的温度场及应力场温度分布情况。(6)利用凹模摩擦接触表面的分形数学模型对环模凹模摩擦过程中的最高温升进行预测并进行分析,确定环模凹模粗糙分形表面最大温升随摩擦因数、滑动速度、材料的机械和热性能参数、真实接触面积、名义接触面积以及表面轮廓分形参数等的函数变化规律。本文对农业机械、饲料加工机械的设计、制造具有重要的意义,对于推广柱塞式环模成型机有重要意义,是具有广阔前景的研究课题。更多还原

【Abstract】 In the field of biomass molding, especially ring molding machine molding process, due to the friction and wear of high energy consumption, high cost, greatly weakened the penetration ring molding machine, the ring mold market accept ability has not been high. Thus control friction, reduce wear and improve the energy saving performance, and a reasonable potential of materials to play, such as the friction and wear of research is of material significance in the project.This paper studies done not only provide a theoretical basis for the selection of new biomass ring plunger molding equipment of key parameters, in order to "" twelfth five-year "National Science and Technology Support Program (2012BAD30B0205)" to support, as a lightweight removable ring mold biomass briquette manufacturing part of the key technology research, and the design and manufacture of new biomass ring plunger molding machines provide important theoretical and reference.In this paper, the nonlinear theory of fractal theory to graduate material forming materials-dynamic behavior of the ring mold die friction and wear processes, revealing the wear behavior of the law in the process, while the total amount of wear ring mold die to predict specific. The main contents are as follows:(1) Analyze the causes and forms of biomass plunger ring die molding machine failure, stress analysis of the ring mold and failure analysis to determine the wear ring mold is the main reason for the failure.(2) The use of fractal theory, combined with ring mold die rough surface fractal characteristics derived formulas ring mold die and the material of the contact area, Characterization ring mold die and molding materials rough surface curve fractal method WM function method, using MATLAB computing and modeling capabilities Solidworks establish contact with the surface of fractal geometry and ring die die-molding material surface contact finite element model.(3) Based on fractal theory and rough fractal surface contact model, establish the correctness consider forming materials and ring die die physical characteristics of the ring mold die inner wall wear prediction equation to predict the verification process at the same time explore the ring mold die wear prediction model Typical parameters of the relationship between the average wear rate, simultaneous analysis of different types of materials and material conditions ring ring die die die variation of the total amount of wear worn with time, and realize the die ring mold with a total amount of wear of the wear of time predicted to provide a theoretical basis for the plunger ring mold design.(4) The wear extent predicting for model of ring mold die was verified. And tests were measured by the wear of the ring mold and the two types of different specifications of the die, then correctness of the wear ring mold die predict the degree was verified.(5) On the friction ring mold die coupled thermal and structural analysis to determine the different moments ring mold die temperature and stress field distribution cases, the analysis in different materials and different shaped ring mold material conditions concave ring mold temperature and stress field distribution of mold temperature due to friction caused by heat.(6) The use of die friction contact surface fractal mathematical model for friction ring mold die during the highest temperature forecast and analyzed to determine the ring mold die fractal rough surface with the maximum temperature coefficient of friction, sliding speed, material function of mechanical and thermal variation of performance parameters, the true contact area, the contact area and the nominal surface profile of the fractal parameters.This paper has important implications for agricultural machinery, feed processing machinery design, manufacturing, for the promotion of the plunger ring molding machine application and implementation of large-scale use of biomass resources is important, is a basic theory with deep and broad application prospects research.更多还原