基于磁感原理的结冰探测器参数计算方法

随着我国航空技术的迅速发展，防冰/除冰技术的研究越来越受到重视，系统中结冰探测器直接影响防冰/除冰的效果。文中对一种基于磁感原理的结冰探测器进行了分析，通过建模推导出相关参数的计算方法，并进行了仿真试验。笔者解决了结冰探测器基本设计参数计算的问题，为结冰探测器的设计提供了一种有效方法。     

飞机结冰对飞行安全的影响

飞机结冰是飞行中普遍存在的一种现象,也是造成飞行安全事故的主要隐患之一。本文简述了飞机在飞行中结冰的形成机理,描述了按结冰部位、结冰物理过程和几何形状的结冰分类形式,分析了飞机结冰对飞行性能的影响,最后对飞机防冰、除冰的方法进行了讨论。     

风力机碳纤维叶片表面冰层粘结特性试验研究

风力机叶片表面结冰会破坏叶片翼型轮廓，降低风力机发电效率。因此，开展冰层粘结特性研究可以为风力机防除冰技术研究提供参考依据。基于风力机叶片复合材料的特点，选取型号为T300的碳纤维平板为研究对象，开展表面冰层粘结特性研究。研制了一款粘结力测量装置，提出并制定了结冰样件的制作方法，探究了结冰时长、基体温度及厚度对碳纤维表面冰层粘结特性的影响。试验结果表明，结冰时长对碳纤维表面冰层切向粘结强度的影响较小；液态水通过碳纤维基体与低温环境的传热过程越慢，冰层切向粘结强度越大；传热过程中，基体材料膨胀与收缩的形变量越小，冰层切向粘结强度越高。该研究结果为深入开展风力机防除冰技术研究提供试验基础。     

基于多传感器技术的机场地面结冰检测系统

为了实现对机场地面结冰的检测,给机场除冰提供数据和参照,利用两种光纤式结冰传感器,以及自制的对射式传感器、摄像头、温度传感器等多种传感器构成结冰检测硬件系统,结合各传感器响应特点进行数据融合,达到测量机场地面结冰的厚度、速率,识别明冰、淞冰、混合冰等各种冰型的目的,并最终输出一个供除冰参考的结冰严重程度.     

气候环境实验室地面结冰云雾模拟控制系统设计

飞机结冰会引起飞机气动特性、动力系统性能改变,甚至造成飞行事故。地面结冰云雾模拟设施作为一种模拟飞机飞行结冰条件的重要设备,常用于飞机防除冰系统功能验证。针对气候环境实验室结冰云雾试验条件需要,在对地面结冰云雾模拟系统进行研究的基础上,对适用于气候环境实验室的结冰云雾模拟系统进行了设计。对系统关键设计技术、系统功能及组成进行了分析,并对控制系统方案进行了详细阐述。试验表明,控制系统人机界面友好,运行可靠,能够满足液态水含量、雾滴直径参数的精确调节,产生符合试验所需的结冰环境。     

钢轨表面结冰积雪分步处理装置设计

针对在恶劣环境影响下,钢轨表面结冰积雪现状,通过对现有钢轨表面结冰积雪处理装置的结构创新,设计了一种钢轨表面结冰积雪分步处理装置.通过短波红外加热除雪融冰、轨面冰渣清扫、木纤维块初次吸水、热对流表面蒸发和木纤维块最终吸水,实现处理钢轨表面结冰积雪的目的;该装置的应用提高了钢轨表面除冰除雪的效率,优化了处理效果,可以避免...     

可识别冰型的光纤结冰传感器

现有结冰传感器没有识别冰型的能力或识别冰型的可靠性偏低。针对这个问题,提出了一种能以较高可靠性识别冰型的光纤结冰传感器。在介绍传感器光学结冰探测原理和分析光路的基础上,设计出了此传感器,并在实验室环境下模拟传感器结冰,通过大量的试验,验证了其结果的有效可靠。最后得出结论:该传感器可用于对物体表面冰型(明冰和霜冰)及结冰厚度进行较高可靠性的识别和定量探测,具有广阔的应用前景。     

多功能飞机除冰车的结构设计

介绍了多功能飞机除冰车的结构设计以及技术性能和设计要点。这种多功能飞机除冰车是以斯太尔二类底盘为基础设计制作的后部车厢,具有高空作业系统、除冰系统、防冰系统、复合行走系统和除冰液加热系统。其主要功能是清除待起飞飞机机身、机翼表面上的结霜、积雪和结冰并可对飞机进行高空位置检查、维护和清洗等作业。     

结冰风洞腹撑系统研制及动态特性分析

飞行器在高空飞行时由于外表面结冰而导致的坠毁惨剧多次发生,研制高精度的、用于飞行器大载荷模型结冰试验的结冰风洞腹撑系统对飞行器的防除冰技术的研究具有重要意义。完成了结冰风洞腹撑系统总体结构方案;针对腹撑系统所处的恶劣环境,通过自主创新设计,研制了全新的迎角、侧滑角机构的结构形式。使用大型通用有限元软件 MSC. Nastran,对腹撑系统的强度、刚度和动态特性进行了研究,同时总结了设计制造过程中的不足。调试、精度检测、负载性能试验表明该系统达到了初步设计目的。     

高压输电线路除冰技术综述

针对近年来输电线路遭受严重覆冰导致电线舞动、断线和杆塔倒塌等现象,提出了多种线路除冰方法。首先介绍了热力融冰法、机械除冰法和自然除冰法等常用的几种除冰方法,并分析了各除冰方案的利弊。然后介绍了当前的研究热点机器人除冰方法,结合几种典型的除冰装置,对除冰机器人的除冰机构、行走机构以及能量采集系统进行了介绍。最后对除冰技术的发展趋势进行了展望,并提出防冰、智能除冰和复合除冰等新型除冰理念,为线路除冰技术的发展提供有力保障。     

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。     

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.     

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.     

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.     

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。     

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.     

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...