变径悬臂搅拌轴临界转速的近似计算方法

针对工业上常用的变径悬臂搅拌轴,HG/T 20569中没有相应的临界转速计算方法,为找到简便的近似计算方法,使用ANSYS计算了3个算例的临界转速,并与HG/T 20569中悬臂与跨间二轴段直径相等、作用集中质量的悬臂轴的计算公式进行对比,经数据对比和理论分析,认为在计算变径悬臂搅拌轴的临界转速时,可以采用该公式,将变径轴的质量折算为当量质量来近似计算。

变径细长轴类零件的旋风铣削方法研究

提出了一种用旋风铣削代替车削加工变径细长工件的加工方法。介绍了该方法的加工原理和刀具与工件的相对运动关系,设计了数控变径旋风铣床。此加工方法可以有效地提高变径细长工件的径向尺寸精度、表面质量及生产效率,减小工件表面的形状误差,具有广泛的工程意义。

基于响应面法的变径空心轴优化设计

针对大学生方程式赛车传动轴零件,为满足轻量化要求,提出了一套基于数学模型初始优化与ANSYS有限元分析相结合的设计方法。以变径空心轴的横截面积为优化目标,各段壁厚为设计变量,建立空心轴轻量化模型。根据数学模型求解得出的设计参数进行UG参数化建模,将UG模型和ANSYS进行关联设置后,利用ANSYS Workbench模块对空心传动轴的刚度、强度进行有限元分析。为了实现轻量化设计,采用最佳空间填充方法建立响应面模型,并基于多目标优化设计方法对响应面模型进行迭代优化得到最优解集。仿真结果表明空心轴在满足刚度、强度的要求下,相比初始优化模型减重10%。较为系统地介绍了尺寸零件的设计及优化分析过程,为同类机械零件的设计优化提供了一定的参考依据。

沥青混合料摊铺机螺旋分料器螺旋轴的仿真分析

为了研究螺旋分料器螺旋轴的承载能力,在ANSYS中建立螺旋分料器螺旋轴模型,以变径变螺旋分料器螺旋轴为研究对象,借助有限元仿真软件,确定变径变螺旋轴的最大形变处,研究变径变螺旋轴直径对共振频率和形变的影响。结果表明:变径变螺旋分料器在中间一段的形变量最大,两边逐渐减小;最大形变量随着变径变螺旋轴直径的增大而减小,但适当增大直径有利于降低共振频率,提高承载能力。

Energy conversion of rocks in process of unloading confining pressure under different unloading paths

Based on energy theory and tests of rocks with initial confining pressures of 10, 20 and 30 MPa under different unloading paths, the processes of strain energy conversion were investigated. The absorbing strain energy for axial compression, the dissipating strain energy for plastic deformation and cracks propagation, the expending strain energy for circumferential deformation, and the storing and releasing elastic strain energy were considered. Unloading paths included the condition of fixing axial pressure and unloading axial pressure, increasing axial pressure and unloading confining pressure, as well as unloading axial pressure and confining pressure simultaneously. Results show that expending strain energy for circumferential deformation has mainly evolved from absorbing strain energy for axial compression in three unloading paths during unloading processes. Dissipating strain energy is significantly increased only near the peak point. The effect of initial confining pressure on strain energy is significantly higher than that of unloading path. The strain energy is linearly increased with increasing initial confining pressure. The unloading path and initial confining pressure also have great influence on the energy dissipation. The conversion rate of strain energy in three paths is increased with increasing initial confining pressure, and the effect of initial confining pressure on conversion rate of strain energy is related with the unloading paths.

新能源客车总装线轮胎螺母拧紧机工艺设计方案及应用

为了提高轮胎装配质量及精度,且满足客车柔性生产的要求,新能源全承载客车制造工艺中应用了变轴变径轮胎螺母拧紧机设备,本文就变轴变径螺母拧紧机设备工艺设计方案、主要工艺参数、主体结构设计、应用效果等方面进行了重点阐述。

叠螺式畜禽粪污脱水设备的设计

规模化养殖在大大提高畜禽产品产量的同时,养殖场畜禽粪污的排放量也急剧增长,对环境造成了严重的污染。由于畜禽粪污中含有有机物和氮、磷、钾等营养成分,经过一定的固液分离预处理可进行资源化利用。因此,笔者设计了一种叠螺式畜禽粪污脱水设备,设备采用变径螺旋轴、不等螺距旋片及动定环过滤结构,使粪污在推进过程中受高压挤压脱水。经验证,设备脱水效果达到设定值,相比其他机械脱水设备噪声小、运行成本低、不堵塞且有自我清洗能力,可进一步推广应用。

Short-axis substitution approach on ladder-type benzodithiophene- based electron acceptor toward highly efficient organic solar cells

Short-axis substitution, as an effective way to change the optical and electronic properties of the organic semiconductors for organic photovoltaics(OPVs), is a readily approach to modify non-fullerene acceptors, especially for the linear fused rings system. Here, two new fused-ring electron acceptors(CBT-IC and SBT-IC) were designed and developed by short-axis modification based on the dithienyl[1,2-b:4,5-b′]benzodithiophene(BDCPDT) system. Combined with a medium bandgap polymer donor J71, both of the OPV devices exhibit high power conversion efficiency(PCE) over 11%, and ～70% external quantum efficiencies. To better understand how this kind of substitution affects the BDCPDT based acceptors, a comparative analysis is also made with the the plain acceptor BDT-IC without this modification. We believe this work could disclose the great potential and the versatility of BDCPDT block and also enlighten other ladder-type series for further optimization.