内燃式压缩机动力学分析

将传统内燃机与往复活塞式压缩机工作原理、技术及结构进行集成,提出了一种可方便地将热能转换为气体压力能的内燃式压缩机.建立了等效动力学模型,采用MATLAB软件对其进行了动力学仿真计算.给出了内燃式压缩机一个工作循环中曲轴瞬时转速与转角之间的关系曲线,确定了曲轴速度波动系数与飞轮转动惯量之间的关系,为内燃式压缩机的工作平稳性设计奠定了基础.     

颚式破碎机建模仿真的研究

论文将颚式破碎机的曲柄摇杆机构作为研究对象,根据颚式破碎机的工作原理及结构,提出了曲柄摇杆机构中曲柄的质量及转动惯量的计算方法,并对其进行比较分析,其中包括飞轮、主轴、偏心轴装置、连杆及肘板的质量及转动惯量的计算。在此基础上,利用Matlab仿真软件对颚式破碎机机构进行运动学、动力学进行仿真及研究。     

内燃式压气机概念设计

为解决传统的内燃机-往复活塞式压气机组合系统存在的效率低、成本高等问题,采用将传统内燃机与往复活塞式压气机工作原理、技术及结构集成的方法,提出一种直接利用内燃机活塞的直线往复运动实现压气功能的内燃式压气机方案。根据其工作原理提出分别采用液压蓄能器、组合弹簧和飞轮提供回程动力的三种设计方案,并采用评分法对其进行分析和选择。根据选出的方案完成概念设计。     

内燃动车车体与动力包悬挂局部振动分析

为了研究采用动力包作为动力源的出口内燃动车的平稳性以及解决动力包与车体安装位置区域存在局部振动过大的问题,采用实验与仿真相结合的方法,得到了内燃动车的平稳性指标,分析了动力包安装位置处的车体局部大刚度和地板隔振器刚度的合理取值对局部振动的影响规律。结果表明:内燃动车的平稳性指标为优级,车体与动力包之间没有耦合振动;车体局部加大刚度对减小车体平稳性指标测点的横向振动有利,平稳性指标测点的垂向振动略有增加;车体地板铺设隔振器能显著减小车体的局部垂向和侧向振动。该研究结果可为实际工程应用提供参考。     

顶置式水冷却装置可靠性设计

介绍了内燃动车组用顶置式水冷却装置的技术特点,总体结构,采用ANSYS有限元仿真分析软件仿真计算和试验验证的方法验证水冷却装置的可靠性,结果表明新研制的顶置式水冷却装置能够满足内燃动车组的要求,其技术可为同类产品提供较好的借鉴作用。     

基于内燃式压气机曲轴系多体动力学仿真与响应分析研究

通过应用仿真分析软件ADAMS进行模拟,完成了内燃式压气机的运动学及动力学模拟和仿真分析,得到在压气机工作周期运转过程中主要部件如活塞、连杆和曲轴等的运动学及动力学特性参数曲线;应用有限元分析软件ANSYS建立了曲轴系柔性体的有限元模型,并对曲轴系进行模态和静力学分析,探讨和研究了曲轴系在刚性体与柔性体状况下的受力状态,为内燃式压气机的曲轴系进一步优化设计奠定了一定的基础。     

基于SIMPACK的振动贡献量及舒适性计算分析

通过对某出口内燃动车利用SIMPACK动力学分析软件建立刚柔耦合模型,计算了车辆在不同运行速度工况下,车辆运行平稳性和舒适性;并对车辆由轮轨激励和柴油机组激励进行振动贡献量分析。计算结果表明在各运行速度下,车辆的垂向平稳性等级均为1级,评定为优;在20 km/h时舒适度为1级,40 km/h和60 km/h时为2级,80 km/h和100 km/h为3级;在低速(20 km/h)时,机组激励大于轮轨激励;随着运行速度的增加,轮轨激励的贡献量逐渐增大,机组激励的贡献量逐渐减小。     

用数字仿真法精确计算飞轮的转动惯量

本文利用数字仿真法精确计算飞轮的转动惯量,其方法简单准确,在机械动力学中具有普遍的适用意义。     

内燃式水平对动空气压缩机的多工况动态特性分析

针对传统的内燃机驱动的活塞式空气压缩机工作过程中振动大,噪声大的问题,提出了内燃式水平对动空气压缩机原理方案,基于虚拟样机技术建立了内燃式空气压缩机曲轴轴系的动力学仿真模型。采用ADAMS软件对其进行了多种工况下的运动学和动力学分析,给出了作用在曲轴上的动态载荷及变化规律。运用有限元分析软件ANSYS对曲轴进行了模态分析,得到了曲轴前六阶模态的振型和响应的频率。建立了曲轴系刚柔混合体动力学模型,完成了内燃式水平对动空气压缩机曲柄连杆机构多柔体动力学仿真。     

约束活塞型内燃式水泵阀式配流系统工作特性研究

提出约束活塞型内燃式水泵的概念并阐述其工作原理，建立了阀式配流系统的动力模型。给出约束活塞型内燃式水泵主体部分及进水阀和出水阀、的动力方程，并对该阀式配流系统的工作特性进行仿真研究。结果表明：阀式配流系统缸内压力在进水阀和出水阀打开的瞬时有较大的阶跃和脉动，出水阀阀片的移动速度在缸内压力最大时达到最大，在缸内压力最小时达到最小；在阀的固有频率（即约束活塞型内燃式水泵工作频率的3倍）附近，阀的容积效率最低。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...