天然气工业2017，Vol.37Issue(8)：102-107,6.DOI:10.3787/j.issn.1000-0976.2017.08.013
天然气流量计量标准装置的工艺流程优化
Process optimization of a natural gas flow measurement standard device
摘要
Abstract
The pipe fittings and equipments in the natural gas measurement standard process are diverse and their influential factors are complicated.Their effects on the measurement performance of a measurement standard device will emerge gradually after they are put into operation,and the rectification is quite difficult.Therefore,the accuracy of the flow measurement standard device can be improved effectively by optimizing its process scientifically in its initial stage of construction.In this paper,it was proposed to optimize the process of a high-pressure large-capacity natural gas measurement standard device by using 3D simulation technology of fluid mechanics (FLU-ENT).This method can offer a stable gas medium for the operation of this standard device and eliminate the effects of pipe vibration and noise on the measurement performance of the device,so as to improve the accuracy of natural gas flow measurement.In the meantime,the typical process pipe fittings (e.g.pipe elbows and rectifiers) were taken as examples to analyze the flow fields inside the pipes under different working conditions by means of modeling and simulation calculation.And accordingly the distribution laws of flow fields were figured out.It is indicated that the effect of upstream elbows on the downstream flow pattern can be reduced by adding manifolds at the standard branch of calibration process and the upstream of calibration branches;and that the effect of flow patterns on calculation results can be reduced and the accuracy of a measurement standard device can be improved by installing rectifiers at the position about 10 d (d refers to the diameter of a standard branch) distance to the upstream of a detected flowmeter and an ultrasonic reference flowmeter.This method is applied to the construction and process optimization of a working-level standard device at the Wuhan sub-station of the national large-capacity oil and gas metering station.Based on check results,the measurement uncertainty of the working-level standard device is 0.29％ (k =2),reaching the domestic advanced level.关键词
天然气/计量标准装置/计量性能/准确度/流体力学/工艺流程优化/模拟仿真/湍流模型流态/国家石油天然气大流量计量站Key words
Natural gas/Measurement standard device/Measurement performance/Accuracy/Fluid Mechanics/Process optimization/Simulation/Flow pattern of turbulence model/National large-capacity oil and gas metering station引用本文复制引用
秦云松,张吉军,林媛媛..天然气流量计量标准装置的工艺流程优化[J].天然气工业,2017,37(8):102-107,6.
