共查询到20条相似文献,搜索用时 15 毫秒
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本文介绍了一种基于分子流传感元件的真空腔体漏率测量方法,该方法通过分子流传感元件测量真空腔体整体漏率,采用的测量装置由气体流量测量系统、真空抽气系统、恒温系统等部分组成。在测量系统中,流经传感元件的气流处于分子流状态,通过测量传感元件两端的差压,计算质量流量,可以得到真空腔体的整体漏率。实验中对多个真空腔体漏率的测量结果表明,该方法可以实现对10-5-10-3 Pa·m3/s量级真空腔体漏率的准确测量。除去本底漏率之后,测量结果与理论结果高度拟合,测量结果显示最小偏差为0.05%,最大仅为0.62%。且通过改变分子流传感元件流导值和差压变送器量程可以进一步扩展该方法可测真空腔体整体漏率范围。 相似文献
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The pressing current problems of increasing the level of the metrological service of instruments for measuring liquid mass flow rate are presented. The action principle, metrological characteristics, results of investigations of the State primary standard of the unit of liquid mass flow rate, and the verification scheme regulating the order of transferring the size of the unit to working measurement standards are presented. 相似文献
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Gerasimov A. P. Ivanov V. P. Krasavin V. M. Lakhov V. M. Rainchik S. V. Semenova O. K. 《Measurement Techniques》2005,48(4):374-380
A mathematical model of the flow of a gas in Laval nozzles is analyzed. The model is used to obtain equations for measuring the mass and volume flow rates of a gas.__________Translated from Izmeritel’naya Tekhnika, No. 4, pp. 44–48, April, 2005. 相似文献
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The existing MI 1538-86 recommendation regarding the measurement of mass flow rate using critical nozzles is analyzed. It is shown that there are contradictions between the MI 1538-86 recommendations and the conditions for the conservation of mass, energy and momentum, due to the simplified assumptions made, which introduces a systematic error into measurements of mass flow rate. 相似文献
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为了探明压铸生产过程中熔融铝合金速度、压力场对模具侵蚀过程的影响及其作用机理,本文设计动态侵蚀试验,通过计算流体动力学仿真软件计算旋转试样圆周区域速度场和压力场分布状态,观察试样表面的宏观形貌并利用SEM、EDS作元素微量分析。结果显示:试样前端与尾端区域速度最大,前端与远端之间压力场最大;流体压力场对试样侵蚀的影响属压应力作用,促进原子间的扩散,加快金属间化合物生成的速度,加剧试样表面的侵蚀程度;流体速度场对试样侵蚀的影响属切应力作用,导致生成并附着于试样表面的金属化合物层剥离,造成深坑状的腐蚀形貌。 相似文献
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本文介绍了用经检定的标准容量瓶测量液相色谱仪的泵流量的方法,比较了用该方法与用《JJG705-90实验室液相色谱仪检定规程》的标准方法测得泵流量及泵流量设定值误差、泵流量稳定性误差的标准不确定度的差另,阐明了该方法的替代标准方法的合理性。 相似文献
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A method is developed for determining the mass discharge and consistency of a pipe flow carrying a suspension under pressure. Mass discharge and consistency are determined by using readings of the power used by the hydraulic dredger which moves the flow. 相似文献
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介绍了目前常用的蒸汽流量测量方法--直接测量法,对其测量原理、特点及测量误差进行了分析。针 对系统工况负荷变化频繁、蒸汽流量经常出现大幅度波动、直接测量流量误差较大的问题,提出了一种流量软测 量,即无节流元件的蒸汽测量方法。利用此方法对蒸汽流量进行计算,并与实际流量计测量值对比,得出在流量波动时,流量计测量误差为10%,而软测量误差最大不超过5%。 相似文献
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It is shown that the transfer into a recording instrument of a measured volume flow rate of low-viscosity liquids in the form of a PWM-signal, and also software and hardware for carrying out the functions of monitoring and self-diagnostics and for eliminating the random component of the errors and subregulation using external crossing components in combination with the use of the M1821BM85A microprocessor, ensures the functional reliability of the monitoring and measuring system, thereby satisfying the requirements for their use in industrial and transport systems. 相似文献
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乳化炸药连续生产线的油、水相流量采用流量计测量,对这一重要的物理量,有一定的工艺控制要求,它表征生产线生产能力和质量,文章阐述了流量的测定与测量数据的处理。 相似文献
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梯度相关法测量两相流流量的精度与离散性研究 总被引:6,自引:0,他引:6
借助一种新的传感器布置与信号处理方法,能够测量真正的平均流速与流量。通过对气一固两相流体的实验研究,证明了梯度相关理论与实验相符。针对长时间连续测量中出现的互协方差梯度波动问题,对光学传感器的数学模型与互协方差梯度计算方法进行了修正,提高了测量精度。 相似文献
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Dzhabbarov R. R. Kayumov M. A. Khakimov O. Sh. Cherepanov V. Ya. 《Measurement Techniques》2004,47(4):393-396
An improved method is considered for measuring the cooling rate of a calorimeter thermal cell in the determination of the total thermal resistance of a textile material. Experiment confirms the improved accuracy. 相似文献
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