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本文介绍了用标准涡街流量传感器组合比较法的流量标准装置、检测原理和数据处理方法,解决了大口径气体流量仪表的标定问题。 相似文献
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涡街流量传感器原理与应用 总被引:1,自引:0,他引:1
涡街流量传感器适用于测量液体、气体、蒸汽、低温和各种腐蚀性介质,被广泛应用于石油、化工、轻工、冶金和电力企业中,本文阐述了涡街流量传感器的设计原理、构成和应用。 相似文献
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利用数值计算的方法,实现对涡街流量传感器中压力场动态分布特性的研究。数值计算采用湍流理论中的k- 模型并结合CFD技术进行,以SIMPLE算法解离散控制方程。数值计算得到的旋涡脱落频率与试验结果相近,误差不超过7%,证明数值计算方法的有效性,并在此基础上通过对涡街流场中压力场分布特点的分析,给出检测旋涡信号的最佳区域。从分析旋涡在流场中动态变化过程入手,深入探讨引发压力场变化规律的流场内部机理。 相似文献
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介绍了气体涡街流量变送器的原理和方法,变送器由信号获取单元和信号处理单元组成,集成了信号变换、信号处理和信号显示与输出等功能。实际应用表明变送器性能指标达到了设计要求。 相似文献
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多功能压力传感器与现场总线技术 总被引:2,自引:1,他引:1
传统的差压传感器一般由差压敏感元件和温度补偿网络构成,输出信息量少。在线性及温度误差的补偿方法通常采用无源网络对传感器的两个端点进行补偿,比较粗糙,补偿精度较低,对静压带来的误差无法补偿。本文介绍了HART协议智能扩散硅差压变送器的组成原理及应用,阐述了扩散硅多功能传感器的特点,以及非线性及温度误差的补偿方法。 相似文献
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任玉峰 《工业仪表与自动化装置》2006,(6):56-58
简要介绍使用差压式流量传感器进行一般气体流量测量时的温压补偿方法;指出了差压方式流量传感器测量一般气体的通用流量温压补偿公式,并写出了公式的推导过程;与线性流量传感器温压补偿方法进行对比,强调指出了采用差压式流量传感器时进行温压补偿的注意要点.对公用工程中的一般气体的流量计量工作有一定的指导作用. 相似文献
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涡街流量传感器应用问题的探讨 总被引:2,自引:0,他引:2
王京安 《仪表技术与传感器》1996,(8):46-48
本文详尽地分析了涡街流量传感器应用中存在的问题、造成问题的原因,并介绍了涡街流量传感器原理及结构。 相似文献
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基于子波变换消噪原理,结合涡街流量传感器的实际应用,提出了一种适用于涡街流量传感器频率计数的子波滤波方案,同时给出了滤波级数的选取方法.基于涡街流量传感器工作原理,这种改进的重构计数能够达到计量要求.通过对实测信号的分析,证实了方法的有效性. 相似文献
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0 INTRODUCTIONWhen a bluff body is placed in a flow stream,vortices form behind it and shed alternately from eachside. The shedding frequency keeps in a direct ratiowith the mean velocity over a wide range of Reynoldsnumbers.The idea of building a flow meter based on theassumption of a constant Strouhal number was firstproPOsed by Roshko, whose work indicated that theStrouhal number remains at an almost constant valueof 0.2 in the Reynolds number ranged 300 < Re <2 x l0s .For about thr… 相似文献
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在DN25水流量标准装置上对装有梯形漩涡发生体的涡街流量计在低雷诺数下进行试验研究,利用数字信号处理方法(频谱分析方法)得到涡街脱落频率,较传统模拟信号处理方法在保证较好线性度的基础上,有效地扩展了测量下限。绘制雷诺数—仪表系数曲线,发现梯形发生体在低雷诺数下仪表系数K呈递减趋势,当Re>2 000时K趋于常数,这与圆柱发生体在低雷诺数时曲线递增的趋势截然相反。通过分析得知,管道内流速分布的影响、发生体形状的影响和流速与频率关系的影响是导致上述变化趋势的3个主要影响因素。 相似文献
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HU Xiaodong ZHOU Yiqi FANG Jianhua School of Mechanical Engineering Shandong University Jinan China MAN Xiliang Shandong Construction Machinery Group Co.Ltd Jinan China ZHAO Zhengxu School of Computing Derby University Derby DE GB UK 《机械工程学报(英文版)》2007,20(2):88-93
The pressure loss of cross-flow perforated muffler has been computed with the procedure of physical modeling,simulation and data processing. Three-dimensional computational fluid dynam-ics (CFD) has been used to investigate the relations of porosities,flow velocity and diameter of the holes with the pressure loss. Accordingly,some preliminary results have been obtained that pressure loss increases with porosity descent as nearly a hyperbolic trend,rising flow velocity of the input makes the pressure loss increasing with parabola trend,diameter of holes affects little about pressure loss of the muffler. Otherwise,the holes on the perforated pipes make the air flow gently and meanly,which decreases the air impact to the wall and pipes in the muffler. A practical perforated muffler is used to illustrate the available of this method for pressure loss computation,and the comparison shows that the computation results with the method of CFD has reference value for muffler design. 相似文献
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基于信息熵的钢制薄壁内压容器试验压力 总被引:1,自引:2,他引:1
基于钢制薄壁内压容器模糊静强度的信息熵分析,从控制钢制薄壁内压容器模糊静强度在正常操作与压力试验时模糊可靠度的角度,对其安全系数与试验压力系数进行探索。研究表明,从等可靠度的观点,(1)钢制薄壁内压容器模糊屈服强度可靠度在正常操作时应不低于0.99354,在气压与液压试验时应分别不低于0.97260与0.7925;模糊爆破强度可靠度在正常操作时应不低于0.99999999140,在气压与液压试验时应分别不低于0.99999999140与0.999990226。(2)钢制薄壁内压圆筒屈服安全系数应不小于1.45,抗拉安全系数应不小于1.80;钢制薄壁内压球形容器屈服安全系数应不小于1.40,抗拉安全系数应不小于1.85;扁平绕带式容器屈服安全系数应不小于1.35,抗拉安全系数应不小于1.95。(3)钢制薄壁内压圆筒试验压力系数在气压试验时应不小于1.04,但不大于1.16;在液压试验时应不小于1.04,但不大于1.26。钢制薄壁内压球形容器试验压力系数在气压试验时应不小于1.04,但不大于1.19;在液压试验时应不小于1.04,但不大于1.26;扁平绕带式容器试验压力系数在气压试验时应不小于1.04,但不大于1.16;在液压试验时应不小于1.04,但不大于1.28。 相似文献
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Experimental and numerical study of the flow characteristics of a novel olive-shaped flowmeter (OSF)
A novel differential pressure flowmeter with an olive-shaped flowmeter (OSF) is proposed and investigated both experimentally and numerically. The streamline, pressure and velocity are obtained and numerically analysed. The results indicate that the proposed OSF exhibits less permanent pressure loss than the orifice plate flowmeter (OPF). The pressure also tends to be more stable in the OSF, which ensures high measurement accuracy and repeatability. The OSF is superior to the OPF in terms of relative pressure loss, streamline distribution, pressure distribution and velocity distribution. In the experiment, an oil pump transported diesel oil into the measurement pipe, through the check valve, filter, pressure-regulating container, and flow-regulating valve, before it was finally returned to the fuel tank. The experimental results showed that the pressure loss of the OSF was only about 14.94% of that of the OPF under the same conditions. The pressure loss curve of the OPF increased rapidly by up to 2,700 Pa with each 1 m3/h increase in the flow rate, whereas that of the OSF increased only slightly. 相似文献