摘要
基于音速喷嘴式气体流量标准装置校准原理,对标准装置的测量精度、密封性和背压比等计量特性进行了试验分析研究。通过固定音速喷嘴螺母不同拧紧力矩对比试验,验证了音速喷嘴安装不到位所导致的内部泄漏会给测量结果造成较大误差。背压比试验得出,实际临界背压比可由音速喷嘴所在具体装置通过试验比较后获得,通过调整抽风机压力,适当降低实际背压比,可保证标准装置的测量精度,使标准装置的稳定性达到0.09%;同时评定的标准装置的扩展不确定度为0.38%(k=2)。试验分析对标准装置的检测及量值溯源具有一定的借鉴意义。
Based on the calibration principle of the sonic nozzle-type gas flow standard device, the measurement characteristics of the standard device, such as measurement accuracy, sealing performance and back pressure ratio, were experimentally analyzed and studied. The comparison test of the different tightening torque of fixed sonic nozzle nut verified that the internal leakage caused by improper installation of sonic nozzle would cause a significant error to the measurement result. The actual critical back pressure ratio can be obtained by comparing the specific device where the sonic nozzle is located. By adjusting the suction fan pressure and appropriately reducing the actual back pressure ratio, the measuring accuracy of the standard device can be guaranteed, and the stability of the standard device can reach 0.09%. The extended uncertainty of the standard device is 0.38%(k=2). The experimental analysis above has a particular reference significance for the detection and value traceability of the standard device.
作者
杨文武
贺敬良
车跃跃
YANG Wenwu;HE Jingliang;CHE Yueyue
出处
《计量与测试技术》
2022年第5期36-40,共5页
Metrology & Measurement Technique
关键词
音速喷嘴
气体流量标准装置
密封性
背压比
sonic nozzle
gas flow standard device
sealing performance
back-pressure ratio