摘要
为保证水泵试验台精度和试验稳定性,除了选择高精度的测流设备外,还应有高精度的流量原位标定装置。提出了称重-容积法原位标定方法,在水泵试验台上实现了流量计的正、反向原位标定。根据系统设计目标,对供水加力水泵、称重桶、水池、气动换向器和标准金属量器分别进行了选型和计算。依据测量不确定度理论,标定系统不确定度主要由标准量器、计时器、换向器和容积法标定传感器装置等不确定度组成,计算了称重桶容积法、换向器和整个系统的不确定度。经试验和计算,系统扩展不确定度为0.136%,系统流量稳定度为0.0212%。计算和压力脉动测试结果表明采用溢流供水池和变频调速加力泵相结合的方法可保证系统标定时压力稳定。称重-容积法原位标定方法将称重法和容积法有效的结合起来,在水泵试验台中成功地得到了应用。该方法达到了既保证精度又降低造价的目的,具有较好的推广应用前景。
In order to assure the accuracy of pump test rig and stability of measurement, an in-situ calibration system with high precision should be equipped besides a flow meter with high precision. A volume-weight method for calibration is brought out to achieve bidirectional calibration. According to the design objective, the pump, weight tank, pool, commutator and standard measuring cylinder are calculated and selected. Based on measurement uncertainty method, the system uncertainty consisted of uncertainty of standard measuring cylinder, calculagraph, commutator and calibration sensor of volume method. The calculation formulas of these uncertainties are presented. The total expanded uncertainty of system is 0. 136% and the stability of flowrate is 0. 0212%. Results from calculation and pressure pulse experiment indicate that the combination of convert-frequency facility with invariablehess＇ pool can maintain the pressure stability of test. The volume-weight calibration method, which combines the weight method and volume method, can assure the accuracy and also reduce the expensive. It could be applied in similar test rigs .
出处
《南水北调与水利科技》
CAS
CSCD
2011年第4期28-33,共6页
South-to-North Water Transfers and Water Science & Technology
基金
国家自然科学基金资助项目(50809057)
教育部留学出国人员科研启动基金(教外司留[2010]1561号)
关键词
水泵
试验台
原位标定
流量
容积
称重
pump
test rig
in-situ calibration
flowrate
volume
weight
