连续测量活塞式液体流量标准装置的设计和应用

Design and Application of the Piston Type Standard Device for Continuous Liquid Flow Measurement

为获得较高水平的测量不确定度,并在测量过程中使流体保持定常流,设计了以形状规则、尺寸均匀的圆柱体活塞作为关键计量机构的液体流量标准装置。装置通过控制伺服电机驱动活塞作任一匀速直线运动,使活塞均匀等量置换出活塞缸体内的流体,以实现计量功能。研究表明,装置体积测量的准确度与活塞加工精度、机械安装和相关量的测量等有关。在综合考虑各种因素的基础上,通过分析和推导,建立了适合工程实际应用的测量模型和校准模型。经实践应用,验证了装置测量模型设计和应用的有效性。

In order to obtain a higher level of uncertainty, and maintain steady flow of the fluid in measuring process, based on regular shape and uniform size,the cylinder piston is designed and used for the liquid flow standard device as a crucial metering mechanism. Through controlling the servo motor, the device drives the piston to make uniform linear motion and to displace equal amount of fluid inside piston cylinder to realize metering function. The research shows that the accuracy of volume measurement of device is related to the machining precise of the piston, mechanic installation as well as the measurement of relevant quantities. On the basis of comprehensive consideration of various factors, by analyzing and deducing, the measurement model and calibration model are established which are suitable for the practical engineering application. The practice verifies the effectiveness of the measurement model of the device and its design and application.