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51.
采用有限元数值分析法,对长弧形电极非满管电磁流量传感器的权重函数进行了研究,并给出了不同液位下的权重函数分布图谱。计算结果表明,非满管电磁流量传感器的权重函数与管内液体充满度有关,两者呈复杂函数关系。该研究结果为优化非满管电磁流量传感器结构提供了理论依据。 相似文献
52.
结合水煤浆加压气化制合成氨的工艺流程和特点,提出流量计选型和安装时着重考虑的问题,介绍流量计在渭河化肥厂合成氨装置上的应用情况。 相似文献
53.
超声波气体流量测量系统的实现 总被引:1,自引:0,他引:1
超声波气体流量计因为其具有许多优点,在工业上获得越来越广泛的应用。超声波气体流量测量需应用一种新的流量测量技术,因为超声气体流量计工作在噪声较强的场合,且信号微弱。超声波气体流量计信号不能用传统的方法检测,在此,数字平均技术及相关技术得到应用,数字平均技术可使信号得到加强,相关技术可使渡越时间测量更精确,流量测量精度可达±2%。 相似文献
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煤气流量测量一直是仪表检测的难点,锥型流量计为煤气流量测量提供了新的测量方法,本文介绍了锥型流量计在现场的使用情况和特点。 相似文献
58.
A novel configuration of a landfill wellhead was analysed to measure the flow rate of gas extracted from sanitary landfills. The device provides access points for pressure measurement integral to flow rate computation similarly to orifice and Venturi meters, and has the advantage of eliminating the problem of water condensation often impairing the accuracy thereof. It is proved that the proposed configuration entails comparable computational complexity and negligible sensitivity to geometric parameters. Calibration for the new device was attained using a custom optimization procedure, operating on a quadri-dimensional parameter surface evincing discontinuity and non-smoothness. 相似文献
59.
Accurate measurement of water flow rates in large diameter pipelines is a challenge for water companies that need to produce, transport and distribute increasing quantities of water. To a large extent, this challenge results from the impossibility of recalibration of the flow meters within the periodicity established in the metrological regulations since the removal of a large size flow meter from its site of operation in the field and its transport to a calibration laboratory is in most cases technically and economically impracticable. Because of this scenario, this paper presents the pitometry technique as an interesting alternative to solve problems related to the validation of water flow measurements performed by flow measurement systems installed in large diameter conduits. The technique is based on the determination of the water flow rate by mapping the velocity profile of the water flow inside the pipe by means of Cole type Pitot tubes. The water flow rate is determined in a cross section of the pipe located near and in series to the flowmeter to be evaluated. Based on the results obtained in a great number of water flow measurements already performed by applying the pitometry technique in large diameter pipelines in the field, it is possible to conclude that this methodology is perfectly applicable in the validation of the performance of flow meters installed in these conduits solving satisfactorily the issues related to its operation. 相似文献
60.
Experimental data from an oscillating circular piston positive displacement flowmeter are described which focused on leakage flows and wear. This is the second part of a two part paper on the experimental tests, the first part concerned piston movement and pressure loss. In this paper the leakage across the meter is reported for key parameters including: flow rate, liquid density and viscosity, mass of circular piston, surface coating and length of connection pipes. In addition to the average leakage over a period of time, the leakage past a stationary circular piston was measured during a simulated oscillation. Wear tests were run for both stainless steel and carbon pistons to identify the affected areas of piston and chamber. 相似文献