摘要：为改善涡旋压缩机振动,对其传动系统的动平衡进行优化设计。对涡旋压缩机的动平衡系统进行理论研究,通过EXCEL软件提供的规划求解功能得到了动平衡的最优解,理论上通过该方法对上下平衡块的优化设计可以将不平衡量将至0。分析了动平衡系统部件的误差对不平衡量的敏感性,发现相较部件质心轴向位置,其离心力的误差对动平衡系统影响更大。为检验动平衡设计对压缩机振动的价值,在理论上分析了动平衡系统的不平衡量对压缩机振动的影响,并与压缩机振动试验结果比对。振动试验结果表明,动不平衡量与压缩机振动正相关,与理论相符。EXCEL软件应用广泛,程序运行稳定、速度快,不需要自行编写程序,可极大减少设计时间和开发周期,降低设计成本。

摘要：为进一步降低熔丝沉积成形设备的运行成本,同时提高成形效率,设计一种斜壁结构的支撑,基于STL模型提出并实现其自动生成算法.实验证明该支撑结构与常用直壁结构支撑相比,不仅能够有效辅助零件实体的成形过程,而且能够尽可能地减少支撑材料消耗量和成形时间.算法实用可靠,已成功集成至Power RP软件支撑模块中.

摘要：深入分析快速成形制件翘曲变形的原因后,提出一种全新的扫描填充路径——并行栅格路径及其规划算法.按照这种路径能够近似、并行地完成整个待成形二维平面区域的扫描填充过程,在减小XY向温度梯度的同时,均匀化不同位置材料成形后的冷却收缩约束力,使得不同位置材料的冷却收缩趋于同步和均匀,减小了制件的整体翘曲变形量.实验表明,该算法能够在与其他类型路径的规划算法大致相当的时间和空间复杂度下,获得扫描填充性能更加优越的路径.

摘要：以某款平板产品上的塑料按键为例,经前期分析,原设计方案注塑加工过程中易造成残余应力过大的问题。通过设计两种结构方案,分别进行Moldflow和ANSYS Workbench仿真分析,确立方案二为最优设计方案。通过L16(44)正交试验,对工艺参数进行优化。优化后方案二的最大残余应力为26.75 MPa。经仿真分析,方案二的按键力在设计要求范围内。通过优化分析,能够避免产品因残余应力过大,出现变形、开裂、强度不足等情况,对同类型产品在注塑成型分析及应用具有一定的借鉴意义。

摘要：根据ANSYS对熔覆层应力场的仿真结果,指导激光熔覆锤击系统锤击力和锤击频率的选择,采用AT89C52单片机为控制核心,DAC0832模数转换器和步进电机86BYG450A作为执行装置,设计其电源、锤击力、锤击频率和步进电机控制电路,对Fe313的熔覆层进行锤击试验验证。试验表明,系统稳定性良好,锤击频率符合精度要求,锤击使熔覆层的力学性能得到了改善。

摘要：For the data processing of the Rapid Prototyping Manufacturing, Boolean operation can offer a versatile tool for editing or modifying the STL model, adding the artificial construction, and creating the complex assistant support structure to meet the special technical requests. The topological structure of STL models was built firstly in order to obtain the neighborhood relationship among the triangular facets. The intersection test between every edge of one solid and every facet of another solid was taken to get the intersection points. According to the matching relationship of the triangle index recorded in the data structure of the intersection points, the intersection segments array and the intersection loop were traced out. Each intersected triangle was subdivided by the Constrained Delaunay Triangulations. The intersected surfaces were divided into several surface patches along the intersection loops. The inclusion prediction between the surface patch and the other solid was taken by testing whether the candidate point was inside or outside the solid region of the slice. Detecting the loops for determination of the valid intersection lines greatly increases the efficiency and the reliability of the process.

摘要：流体阻力的存在制约了矿浆长距离的高效输送。研究了聚氧化乙烯(PEO)稀溶液对清水及铁矿矿浆输送的减阻特性,自制环管实验装置,考察了PEO浓度对减阻的影响,并考察了PEO对不同输送介质的减阻效果。