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基于PRO/E的装载机工作装置优化设计 总被引:2,自引:0,他引:2
使用PKO/E top-down的建模方法建立了轮式装载机反转六杆机构工作装置的参数化模型,并对工作过程进行运动仿真分析.在确定目标函数、约束条件的基础上应用PRO/E的行为建模模块对虚拟样机进行了优化研究.利用PRO/E软件对装载机工作装置进行运动学仿真具有建模简单、控制容易、动作准确、可视性强、分析全面、编程量少等优点. 相似文献
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对气吸振动盘式精密排种装置吸、排种过程进行了研究,分析了携种过程中种子颗粒受力,建立了受力模型,推导出带动吸种盘运动的机械手动力学特性要求:随着负压值的增大,机械手临界加速度增加;长度方向吸附的种子最容易发生掉落,机械手设计时应满足长度方向不发生掉落的条件。同时,建立了种子颗粒与吸种盘的碰撞运动数学模型,得出种子颗粒不被碰离吸种盘面板的弹回临界速度与负压值的关系。结果表明:随着负压值增大,种子颗粒弹回临界速度增加;长度方向碰撞的种子最容易发生弹回掉落,当碰撞弹回速度大于临界弹回速度时,种子将脱离气流场约束并弹离吸孔。 相似文献
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产品数字化建模是一种将实物产品转换为数字化模型的技术,可快速、准确地创建产品数字化模型,实现产品虚拟设计、仿真分析及优化。该文以联合收割机设计为例,探讨了基于产品数字化建模技术下联合收割机设计与分析的方法,对建模效果进行分析,同时提出未来产品数字化建模技术在农业机械生产及制造中的发展趋势与研究方向。研究成果为农业机械的数字化设计和性能优化提供了有益的经验和指导,为推动农业现代化的进程提供技术参考与借鉴。 相似文献
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旋挖钻机工作装置有限元分析 总被引:2,自引:0,他引:2
采用NASTRAN有限元分析软件对旋挖钻机工作装置进行有限元分析,在NXMASTERFEM中抽取UG模型中面建立几何模型,以shell单元和solid单元为基本单元,建立各部件有限元模型,使用有限元装配方法建立工作装置整体有限元模型,分析了旋挖钻机几种典型工况下工作装置的强度及模态,然后对桅杆进行了屈曲分析: 相似文献
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应用NX MasterFEM对某装载机工作装置进行建立CAD模型装配和有限元模型装配,使用NX NASTRAN有限元分析软件对装载机工作装置进行应力分析,确定工作装置中的各部件在正常工况下是否能够承受相应载荷,是否满足工作要求。 相似文献
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以我国生产的22t挖掘机为研究对象,分析和探讨在Pro/E的软件环境下,通过运用有限元计算方法和运动仿真分析法对挖掘机工作装置运动过程进行分析,提高了挖掘机设计的安全性。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献