摘要：An optimum design of the turbine would need a clear understanding of the influence of blade geometry on a Wells turbine performance. Practically, it is difficult to suggest the optimum geometry for the Wells turbine due to the complex interrelation among important parameters, the solidity, hub-to-tip ratio, aspect ratio, blade sweep of rotor, and so on. In the present study, the effect of blade geometry with the hub-to-tip and aspect ratios of rotor on the turbine performance was investigated with a numerical technique. As a result, the optimum blade geometry is as follows: the hub-to-tip ratio is about 0.7, and the aspect ratio about 0.5 under other constant important parameters, NACA0020 blade with blade sweep ratio of 0.35, and solidity of about 0.67. Furthermore, the detailed flow patterns for blade geometry were also shown and discussed in this paper.

摘要：应用图论知识 ,引入虚联接的概念来研究车身零件装配的优先关系 ,并用相邻矩阵表示 基于装配结构信息的矩阵表达 ,提出车身分总成的提取应满足的数学条件 ,并通过矩阵的排序运算 ,生成所有的装配序列 该方法可以有效地产生分总成 。

摘要：Part and Draft modules of SolidEdge are used to construct 3D solid models and generate part drawings, while ActiveX Automation of VB is used to access engineering database files to realize dimension-driven modification of the designed parts. Moreover, VB plays the enabling role of integrating all work processes of gear pump design, resulting in a comprehensive CAD system.

摘要：CAD process for structure design of box culvert is introduced. It follows the traditional way of culvert design. All working conditions of culvert are taken into account. It can generate load diagram, bending moment diagram and bending moment envelope diagram for a single-hole, double-hole or triple-hole box culvert .That is to say, the whole CAD process for the box culvert structure design is realized with the self-developed system. It has been used to accomplish several projects in China and the results are satisfactory.

摘要：机构尺寸综合的两个基本工具是几何法和解析法 ,适用于位置较少的机构尺寸综合 ,而且解析法求解复杂和不直观 提出计算机辅助几何技术的Stephenson六杆机构近似位姿综合法 先用CAD的几何约束和尺寸驱动技术 ,在多个复合精确和近似位姿情况下构造一个基本六杆模拟机构 ,再根据轨迹和运动综合的原则 ,由基本六杆模拟机构分别创造出轨迹和运动的近似位姿综合模拟机构 计算机模拟结果表明 ,该方法不仅具有简洁直观、求解精度高和重复性好的特点 ,而且可以增加机构综合的规定位置个数 。

摘要：为探讨活性炭吸附C40/4有机蒸汽的性能曲线规律,在不同温度288.15K,293.15K和298.15K下实验测试了活性炭C40/4吸附有机气体甲苯和丙酮的吸附性能,基于langmuir等温吸附理论,从吸附动态平衡的角度,理论分析了吸附性能曲线中参数与温度之间的关系,提出一个经验的langmuir等温吸附曲线模型,它能很好地描述不同温度下的有机蒸汽在活性炭上的吸附性能曲线.模型计算值与实验测试值之间的误差小于6%.为确定活性炭吸附有机蒸汽的吸附量提供了有效的计算模式,从而为有机蒸汽吸附过程的设计、预测和优化提供有益的支持.