摘要
差压波动是气液两相流动的固有物理现象,应用该波动可以测量干度和气液总流量。为了研究差压波动对孔板气液两相流测量的影响,本文在压力0.7～1.0 MPa,气相流量200～400 kg/h,干度0.4～1范围内测量了不同流动工况下的差压波动过程。实验结果表明差压平均值和差压标准差可以反映两相流流动参数的变化,但差压标准差重复性较差;实验范围内差压标准差的重复性变化范围为±0.3%～±18.5%;对于低含液率两相流（LNF〈0.3%）,差压平均值的波动会＂掩盖＂液相流量变化造成的差压值变化;误差传递会导致总流量的预测误差大于干度的预测误差;对于高干度两相流（x〉0.5）,误差传递会导致液相流量预测误差被放大。
Differential pressure fluctuation is an inherent physical phenomenon in gas-liquid twophase flow,which can be used to measure the quality and the whole flowrate.In order to study the influence of differential pressure fluctuation on gas-liquid two-phase flow metering for orifice plate,the differential pressure fluctuating processes under different flow conditions were measured,with the pressure ranging from 0.7 MPa to 1.0 MPa,the gas mass flow rate ranging from 200 kg/h to 400kg/h,and the quality ranging from 0.4 to 1.0,respectively.The experimental results show that the mean value of the differential pressure and the standard deviation of the differential pressure could reflect changes of the flow parameters of the two-phase flow,whereas the standard deviation of the differential pressure is with poor repeatability.In the experiments,the repeatability of the standard deviation varied in the range of ±0.3%～±18.5%.For the two phase flow with low liquid content（LVF〈0.3%）,changes of differential pressure caused by the liquid phase could be ＇masked＇ by the fluctuation of the differential pressure.Due to error propagation,the prediction error of the whole flowrate is larger than that of the quality.For two-phase flow with quality higher than 0.5,error propagation could enlarge the prediction error of the liquid phase.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2016年第10期2136-2141,共6页
Journal of Engineering Thermophysics
基金
国家自然科学基金杰出青年科学基金项目(No.51425603)
关键词
气液两相流
流量测量
差压波动
重复性
gas-liquid two-phase flow
flow measurement
differential pressure fluctuation
repeatability
