长喉颈文丘里喉部取压位置对湿气测量模型影响的试验研究

发布时间：2018-01-03 14:35

本文关键词：长喉颈文丘里喉部取压位置对湿气测量模型影响的试验研究　出处：《机械工程学报》2014年12期 　论文类型：期刊论文

【摘要】：文丘里流量计广泛应用于湿气流量测量领域。为探索长喉颈文丘里管喉部取压位置对其湿气测量模型的影响,从理论上对其各个部分压力降进行研究。设计内径为50 mm、节流比为0.4的文丘里试验样机,取压位置距离喉部入口分别为喉部直径的0.5倍、3.75倍和7倍。在天津大学流量实验室双闭环中压湿气装置上进行试验验证。试验压力为0.2~0.8 MPa,干度为0.5~1。根据试验数据,针对不同的喉部取压位置,分析虚高梯度与L-M参数之间的关系;同时分析差压比K参数灵敏度与液气质量比qml/qmg之间的关系,发现虚高和K参数均受喉部取压位置的影响。建立基于K参数、Froude数、气液密度比的虚高模型和液气质量比模型,通过迭代算法求出气相和液相流量。分析基于不同取压位置的测量模型对湿气两相流气相和液相流量预测结果误差和不确定度的影响,得出取压位置为距离喉部入口3.75倍喉部直径时效果最好的结论,该位置模型气相测量不确定度为5.06%,液相为2.15%。
[Abstract]:Venturi Flowmeter is widely used in the field of moisture flow measurement. The experimental prototype of Venturi with 50 mm inner diameter and 0.4 throttle ratio is designed. The pressure position is 0.5 times of the throat diameter from the entrance of the throat. 3. 75 times and 7 times. The test was carried out on a double closed loop medium pressure wet air device in the flow Laboratory of Tianjin University. The test pressure was 0. 2 ~ 0. 8 MPa and the dryness was 0. 5 ~ 1. According to the test data. The relationship between the virtual height gradient and the L-M parameters is analyzed according to the different pressure extraction positions of the larynx. At the same time, the relationship between the sensitivity of K parameter of differential pressure ratio and the ratio of liquid to gas mass qml/qmg is analyzed. It is found that the virtual height and K parameter are affected by the pressure position of larynx, and the Froude number based on K parameter is established. The virtual height model of gas-liquid density ratio and the liquid-gas mass ratio model. The flow rate of gas phase and liquid phase is calculated by iterative algorithm, and the influence of measurement model based on different pressure position on the error and uncertainty of prediction result of gas and liquid flow in wet gas two-phase flow is analyzed. The conclusion that the pressure position is 3.75 times of laryngeal diameter from the throat entrance is the best. The uncertainty of gas phase measurement is 5.06 and the liquid phase is 2.15.
【作者单位】：天津大学电气与自动化工程学院;天津大学天津市过程检测与控制重点实验室;中国石油天然气股份有限公司规划总院;国家石油天然气大流量计量站成都分站;
【基金】：国家自然科学基金(60974118) 国家高技术研究发展计划(863计划,2007AA04Z180)资助项目
【分类号】：TH814
【正文快照】： 0前言湿气作为气液两相流的一种特殊形态,广泛存在于自然界和工业领域中。ISO/TR11583[1]界定的湿气为气相体积分数大于等于95%的气液两相流。近几十年来,由于传统工业和新兴工业的急速发展,对湿气气液两相流的测量技术提出了越来越高的要求,同时也推动了该项技术更加深入快速

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