共查询到19条相似文献,搜索用时 687 毫秒
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为多圈环形管流量计设计了一个多点差压信号的自动数据采集系统,可用于测量和记录环形管不同位置上差压测点的数据,进而确定各测点位置差压信号与总流量之间的关系,以及研究环形管流量系数的变化趋势.该数据采集系统具有测量精度高,采集速度快,数据实时保存等特点. 相似文献
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提出了一种基于环形管流量计的新型气液两相流流量测量方法.设计了多圈环形管流量传感器,通过对多圈环形管的水平直径上和垂直直径上四个差压信号进行分析,建立了不同位置差压信号与总体积流量和总质量流量的关系模型,并由此获得气液两相流的混合密度,实现了气液两相流分相流量的测量. 相似文献
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受测量技术的局限,目前,用于蒸汽测量的仪表种类少,主要有差压式流量计和卡门涡街流量计(一般只用于低压蒸汽的计量)。我厂蒸汽主要是过热蒸汽,其计量多采用孔板、喷嘴等为节流件的差压式流量计。利用微机实行全参数补偿,对提高差压式流量计的计量准确度,促进企业关联交易、班组成本核算工作开展,有着重要的现实意义。一、工作原理差压式流量计,广泛用来测量气体、液体和蒸汽流量。其原理:对于一定形状和尺寸的节流件、一定的测压位置和前后直管段、一定流体参数情况下,节流件前后的差压ΔP与质量流量qm或体积流量之间有一定函数关系。根据… 相似文献
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目前世界上主流的蒸汽流量测量方法有节流式差压流量计和涡街流量计,这两种方法互有优缺点。除此以外,质量流量计、超声流量计在蒸汽流量测量中也有一些应用。涡街流量计和节流式差压流量计的主要优缺点如表1所示。 相似文献
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Yu-Lin Shen 《中国工程学刊》2016,39(4):413-417
Wall thinning defects in steel pipes are usually localized and are difficult to detect using traditional sensors that have a small coverage and limited measuring range. A distributed fiber sensor, based on the Brillouin backscattering sensing system, has been demonstrated to be able to measure the strain and detect the defect in a pipe accurately. A 1.8 m pipe segment that contains artificial thinning from 13 to 60% of wall thickness at various positions was subjected to an internal pressure of 350 kgf/cm2. Hoop strain distribution along the whole pipe segment was monitored by a single optical fiber. The measured strains compared favorably with strain gauge results. The method proposed in this study shows promising results for the detection of the existence and location of wall thinning defects in long distance pressurized pipe. 相似文献
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摘要:通过安装在不同测点位置的加速度传感器获取了离心泵的空化信号,利用时域和频域分析手段进一步探索离心泵空化的特点和规律。实验结果表明:位于泵壳上的测点B对空化更加敏感,更适宜作为空化监测点;空化前后,振动信号呈现出了先增大又逐渐减小的趋势,且在6kHz和8kHz出现明显的峰值; 5~8 kHz和8~12 kHz频带振动加速度级以及5~12 kHz宽带振动加速度级在空化后都有10dB左右的增大,能够明显的反映出空化的变化趋势,可以作为空化监测的特征量。 相似文献
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分布式光纤管道泄漏检测及预警技术灵敏度分析 总被引:1,自引:1,他引:0
针对管道安全存在的问题,提出了一种基于Mach-Zehnder光纤干涉仪原理的分布式光纤管道泄漏检测及预警技术,利用与管道同沟敷设的光缆中的3条单模光纤构成分布式光纤微振动传感器检测管道沿线的振动信号,可以有效地检测管道沿线所发生泄漏和异常事件.分析和研究了检测系统的测试灵敏度影响因素,并采用不同光缆结构和埋设方式对检测系统的检测灵敏度进行测试.实验结果表明,该检测技术可以检测到1m范围内的人工挖掘信号,在气体管道压力不小于0.2MPa的条件下,可以检测到0.4m^3/min的气体管道泄漏. 相似文献
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针对石化行业中在高温工作状态下的管道测厚问题,本文研究了超声波高温管道测厚方法中的一些影响因素,并实现了一套高温管道超声波测厚的仿真系统。实验中讨论了不同厚度、不同材料、不同噪声水平以及不同温度对超声波管道测厚结果的影响。此外,比较了不同测厚方法对管道厚度测量的影响。实验结果表明,该系统能够较好的模拟高温超声波测厚系统,能够实现高温管道厚度的测量。 相似文献
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Initial ovality is an inevitable problem in the process of pipe bends manufacturing which results in the stress redistribution of the pipe bends working at high temperature. In order to study the influence of ovality on creep life of pipe bends, full-size creep experiment of P92 pipe bend subjected to in-plane bending has been conducted. The creep strains and outside diameters of dangerous positions have been measured. The microstructures of three different positions of the pipe bend were compared through SEM and the results showed the number and size of the carbide precipitation were the largest at the flank of the pipe bend, which indicated that the creep damage developed fastest at the flank. The modified Kachanov–Robatnov constitutive equations were used to stimulate the creep of P92 pipe bends with FEA software. The representative stress, damage and multiaxiality distributions of the pipe bends have been discussed. The FEA results were consistent with the experimental results and the influence of initial ovality on creep life of P92 pipe bends were analyzed. The results showed that creep life of pipe bends reduced by the increase of ovality and their relationship coincided with the parabolic law. 相似文献