摘要
超声流量计基于时间和长度两个基本量来测量平均流速和流量,几何参数的测算准确度对流量计而言十分重要。可采用三坐标机或全站仪测量管壁点及探头点的三维坐标,并由三维坐标推算流量计几何参数及其不确定度。柱面拟合是流量计几何参数推算的难点与关键,利用Lukacs算法实现了流量计管段的柱面拟合过程,并利用Monte-Carlo模拟方法估算了坐标测量引入的不确定度。最后利用仿真实例说明了柱面拟合算法及其不确定度评估的合理性和有效性。
Geometric parameters are very important to ultrasonic flowmeter, which can be used to calculate flow velocity and flow rate based on time and length measurement. The 3-D coordinates of the pipe points and sensor points can be measured with three coordinate machine or total station, from which the geometric parameters and their uncertainties can be obtained for high-accuracy flowmeters. Cylinder fitting is the key issue of parameter calculation. Luk^ics algorithm is adopted in cylinder fitting, while Monte-Carlo simulation method is used for uncertainty estimation. An example of large-diameter flowmeter is given to illustrate the rationality and validity of the two algorithms.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2010年第7期1583-1587,共5页
Chinese Journal of Scientific Instrument
基金
国家"863"计划(2008AA042207)资助项目
