共查询到20条相似文献,搜索用时 93 毫秒
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移动式标准表法气体流量标准装置,可将标准表法气体流量标准装置通过车载的方式运至流量计使用现场进行流量计检定校准工作,但由于标准装置运输过程中和流量计使用现场的路况及动力设备的高度集成等因素的存在,使得抗震设计及其方法研究成为保证移动式标准表法气体流量标准装置在运行过程中稳定可靠的首要问题。该文对一套移动式标准表法气体流量标准装置通过加装弹簧减震杆及气囊减震系统的方法进行抗震优化,并通过一年的实际实验验证,验证了该抗震设计在保证此标准装置及其标准表性能稳定可靠方面的有效性。 相似文献
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本文叙述了装置的基本原理,重点描述了装置的数学模型,对不确定度的来源进行了分析。根据JJF1059-1999《测量不确定度评定与表示》和JJG643-2003《标准表法流量标准装置检定规程》的规定,对气体流量标准装置的测量不确定度进行评定。 相似文献
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流量标准装置是作为流量单位量值统一与传递的标准,其计量精度、可靠性和检测效率非常重要。本文介绍了一种静态质量法与标准表法结合为一体的高精度、宽量程的液体流量标准装置的设计与实现。阐述了具有砝码自动加载系统的量传系统,多泵组系统配置,特殊设计具有降低冲击的储水池,多层隔板和消气过滤器的稳压消气系统,多表位设计和具有吹扫及排水装置的管线系统,可判断内漏的阀门监测系统,高精度换向器系统。分析了具有数据采集及流量评价的测量系统等各关键环节技术和解决方案,并对装置的不确定度进行了研究。 相似文献
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针对基于静态质量法与标准表法相结合的高精度宽量程大口径液体流量标准装置研制这一关键技术问题,通过储水池防波稳流构造、水泵变频调速稳压、稳压罐结构优化及罐内液体状态监测、管路优化布置和管道流场监测等技术集成,形成了集“源-输-管-测”于一体的液体流量标准装置流场稳定保障技术。通过换向智能测控、高精度标准器及自动核查、阀门泄露监测、数据自动识别等技术,提升了装置的可靠性和准确度。 相似文献
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随着非标准流量仪表种类和数量的日益增加,为了保证仪表的测量精度。非标流量仪表的标定要求显得日益迫切。系统采用了国际标准文丘利作为标准表。应用标准流量计“比较法”原理,配合计算机程序控制,建立气体流量标定系统。进行流量计的检定和测试。依据有关的国家检定规程。该装置可对多孔孔板、V锥、楔形、巴类等差压式仪表以及涡轮、涡街、旋进旋涡等流量计进行检定、工业现场流量模拟实验以及风洞实验。通过运行实践证明,该系统测量精度高,稳定性好,标定流量范围宽。 相似文献
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Top-Down策略在产品系列化设计中的应用 总被引:1,自引:0,他引:1
文中介绍了Top-Down策略的优点,对两种不同的Top-Down设计方法的优缺点进行了比较。相比而言,主控模型Top-Down设计法优势更为明显。文中阐述了主控模型Top-Down的设计流程以及利用主控模型Top-Down法进行产品系列化设计的步骤,并以19″标准抽屉为例,对其实践应用进行了验证。结果表明,主控模型Top-Down法能够很好地完成产品系列化设计,是快速完成产品系列化设计的一种好途径。 相似文献
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线阵CCD驱动时序及信号采集系统的设计 总被引:1,自引:1,他引:0
文中设计介绍了一种基于FPGA和ARM的线阵CCD传感器驱动时序和信号采集的实现方法。该系统通过分析TCD1707D线阵CCD的驱动时序,采用Verilog HDL硬件描述语言设计出驱动脉冲电路。CCD正常工作后,产生的模拟信号经过预处理和高速A/D转换送入FPGA的基本宏功能模块FIFO(先进先出数据缓存器),通过异步缓存实现ARM处理器对采集信号的主控及后续应用。线阵CCD驱动时序及信号采集系统,是基于CCD传感器图像处理系统的重要组成部分,经过上位测试平台验证,能够提供准确的数字图像信号。 相似文献
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程扬波 《工业仪表与自动化装置》2008,(1):57-59
信号源类仪器自动检定/校准测试平台是一套与标准测量仪器及被检定/校准设备无关的对信号源类仪器进行自动检定/校准的测试软件平台。该文就该测试平台中的一个关键技术一一检定流程的设计及实现方法进行了详细论述。 相似文献
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In this paper, the algorithms verifying the covariance matrix of the Kalman filter innovation sequence are compared with respect to detected minimum fault rate and detection time. Four algorithms are dealt with; the algorithm verifying the trace of the covariance matrix of the innovation sequence, the algorithm verifying the sum of all elements of the inverse covariance matrix of the innovation sequence, the optimal algorithm verifying the ratio of two quadratic forms of which matrices are theoretic and selected covariance matrices of Kalman filter innovation sequence, and the algorithm verifying the generalized variance of the covariance matrix of the innovation sequence. The algorithms are implemented for longitudinal dynamics of an aircraft to detect sensor faults, and some suggestions are given on the use of the algorithms in flight control systems. 相似文献
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《机械工程学报(英文版)》2018,(6)
Filament winding has emerged as the main process for carbon fiber reinforced plastic(CFRP) fabrication, and tension control plays a key role in enhancing the quality of the winding products. With the continuous improvement of prod?uct quality and e ciency, the precision of the tension control system is constantly improving. In this paper, a novel tension control method is proposed, which can regulate the fiber tension and transport speed of the winding process by governing the outputs of three di erent driven rollers(the torque of the unwind roll, the torque of the magnetic powder brake roller, and the speed of the master speed roller) in three levels. The mechanical structures and dynamic models of the driven rollers and idle rollers are established by considering the time?varying features of the roller radius and inertia. Moreover, the influence of parameters and speed variation on fiber tension is investigated using the increment model. Subsequently, the control method is proposed by applying fiber tension in three levels accord?ing to the features of the three driven rollers. An adaptive fuzzy controller is designed for tuning the PID parameters online to control the speed of the master speed roller. Simulation is conducted for verifying the performance and sta?bility of the proposed tension control method by comparing with those of the conventional PID control method. The result reveals that the proposed method outperforms the conventional method. Finally, an experimental platform is constructed, and the proposed system is applied to a winding machine. The performance and stability of the tension control system are demonstrated via a series of experiments using carbon fiber under di erent reference speeds and tensions. This paper proposes a novel tension control method to regulate the fiber tension and transport speed. 相似文献
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用VB实现PC机与多个MCS—51单片机为主从式通讯的实例 总被引:1,自引:0,他引:1
介绍了在WINDOWS环境下,采用VB6语言实现的PC机与多台MCS-51单片同机主从式通讯方法,并给出了相应硬件线路图、通讯协议及软件流程图,还介绍了该系统在信号采集与色谱数据分析中的应用实例。 相似文献
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Recent studies on staggered labyrinth seals have focused on the effects of different parameters,such as the pressure ratio and rotational speed on the leakage flow rate.However,few investigations pay sufficient attention to flow details and the sealing mechanism,which would be of practical importance in designing seals having higher performance.This paper establishes a theoretical model to study the seal mechanism,thus revealing that leakage is determined by the pressure ratio and geometric structure.Numerical simulation is implemented to illustrate details of the flow field within the seal structure.Viscous dissipation is used to quantitatively investigate the contribution that each location makes to the seal performance,revealing that orifices and stagnation points are the most important positions in the seal structure,generating the most dissipation.The orifice is carefully studied by using the theoretical model.Experiments for different pressure ratios are conducted and the results match well with those of the theoretical model and numerical simulation,verifying the theoretical model and analysis of the seal mechanism.Three new designs,based on a good understanding of the seal mechanism,are presented,with one reducing leakage by 24.5%. 相似文献