【作者】 张志强；

【导师】 刘俊峰；

【作者基本信息】 河北农业大学 ， 农业机械化工程， 2007， 硕士

【摘要】 本文以玉米秸秆压块饲料为研究着眼点，对玉米秸秆的结构特性，压缩特性、流动规律进行了研究和分析，对成型秸秆的特性进行了测定，并对秸秆在机械压扎成型区秸秆的运动情况进行了动态模拟。首先通过对我国秸秆的利用现状，以及畜牧业存在的问题出发论述了秸秆压块的意义，本文认为我国各类农作物秸秆资源十分丰富，但是秸秆利用存在着很大的弊端，焚烧的现象屡禁不止，而秸秆可以作为牛、羊等反刍动物的重要饲料资源。将丰富的作物秸秆变废为宝，转换为块状饲料，是保护生态环境，促进农业可持续发展的重要课题。块状饲料能提高牛、羊的采食率，消化率，对我国现在粮食紧缺，减少饲料用粮有着重要的意义。用机械加压的方法将秸秆压缩成具有一定形状、密度较大的颗粒饲料，已越来越受到人们的重视。本文对玉米秸秆的结构特性与成分进行了分析，主要论述了秸秆的压缩特性和对秸秆的物理机械性能测试，以及对秸秆的前期处理。论文并描述了机械压扎充型区和成型区秸秆的运动状况，并且描述了秸秆的变化规律。在进入机体的物料之间，物料与壳体之间，物料与推运器之间都发生摩擦，使机腔内温度迅速上升，当达到一定值后，粉碎秸秆中的木质素开始软化，粘结力开始增加，在一定程度上充当了成型时的粘结剂。再经过一定的压力、温度作用使物料经过成型孔后形成颗粒饲料。通过单因素试验考察了秸秆不同含水率、不同粒度、及压缩速度对最大成型压力和密度的影响。随环模转速升高、成型孔长度的增加、原料粒度的增加成型秸秆压块密度增加；随含水率的增加压块密度增加，最大成型压力先降低后升高。最后是计算机仿真部分，利用UG／Motion模块建立成型区机构的运动仿真模型，通过对这个运动仿真模型进行运动学或动力学运动分析，动态地观察成型区机构的运动状况，验证该运动机构设计的合理性，并且压轮和压模的转速、和力的变化情况及物料的运动和受力可以以图表的形式输出，同时可以方便地修改仿真模型的参数，实现驱动实体模型的更新，达到优化设计的目的。得出结论：(1)粉碎后的秸秆在不添加任何粘结剂的情况下可经螺旋挤压成型为颗粒饲料，有利于秸秆资源的重复利用，实现秸秆的饲料化，为压块机械的发展奠定一定的基础。(2)通过对秸秆在环模中的运动分析得出物料在压缩过程中经历三个阶段：物料的松散阶段；密度快速增长阶段；滑移阶段。(3)通过对成形颗粒饲料进行特性测定，得出随环模转速升高、成型孔长度的增加、原料粒度的增加成型秸秆压块密度增加；随含水率的增加压块密度增加，最大成型压力先降低后升高。(4)通过对成型区中压轮及模块的受力分析来说明设备在工作过程中的易损部件部位，并分析了目前环模材料的应用情况，为设计压模提供了理论依据。(5)仿真系统针对性强，对秸秆压块机成型区机构的运动状态进行了动态模拟，具有很强的实用性，为秸秆饲料压块机的生产设计提供理论依据。更多还原

【Abstract】 This text research the construction characteristic, compress characteristic and flow regulation of corn straw,and measure the moulding characteristic.The paper simulate the condition of movement at moulding part.At first the paper discuss the significance of compressed maize stalk fodder about using corn straw and some problems at stockbreeding,thought that although there are a lot of corn straw in china, it have some problems,for example unceasing fire insteading feeding it for cow and sheep.it is important of thing for protect environment and promote development of agriculture to make it to compressed maize stalk fodder.It can lighten compress of lack of foodtuff in country to feed the dumb things compressed maize stalk fodder. Pressure of mechanism can make corn straw to nubbly that is high-density and shaping,it is popular for people.The second part of paper analysis construction characteristic and component of corn straw and compress characteristic,do some experimentation about physics and re-disposal of corn straw.The third part sum up the condition of movement and regulaor of corn straw.the corn straw have friction between corn straws,between corn straw and Shelly, between corn straws and pusher, and the temperature rise rapidly in the machine,the corn straws begin melt when the temperature reach a degree.after high-temperature and high-press,straws became stalk fodder.The paper make a conclusion that with the increase of compress speed and different element of water content,smash-granularity, body-spiral by single factor experiments,pressure and density will increase; with increase of element of water content,the biggest pressure will ascend then descend.Fifths paper introduce computer simulation and computer animation, and use UG to make model of mechanism organization.I use UG to observe the situation of the whole mechanism movement, find dynamics analysis to test the rationality of mechanism.The UG can make chart about speed change of Press round and annulus,change of power,and movement of straw.at last,the paper realize excellent turning of design.Finally get a conclusion:(1)Straw comminuted, are formed compressed maize stalk fodder un-added any glutinous by the helix squeezes,, those can be advantage to re-use for straw, and be foundation to developmeng to mechanism.(2) The paper analysis the process of work that Straw- mechanism press straw, and get conclusion that there are three phase: Lax stage; The density increases the stage quickly; the stage of slip to move.(3) With the increase of compress speed and different element of water content, smash-granularity, body-spiral by single factor experiments,pressure and density will increase; with increase of element of water content,the biggest pressure will ascend then descend.(4) The paper said the flimsy part in the work by anlysis power that Press round and Mold piece beared, and describe the condition of material,supply the theory of designing mold piece.(5) Imitate the true system is powerful, simulate the dynamic work situation of mechanism.this is practicability and supply the theory of designing mechanism of straw-compressed.更多还原