The Research On Negative Pressure Drainage Method Of Gas Flow Standard Device

The research and application of flow standard device which has been drawn widespread attention is a vital part in the development of flow measurement and testing technology.Countries have established many kinds of flow standard devices and conducted in-depth research in their technical indexes and characteristics etc..As the energy problem is becoming more and more improtant,the use of gas flowmeter for trade settlement is increasing,and the measurement of the gas flow meter is more and more significant,especially for the need of high accuracy gas flowmeter.In order to settle these problems,a set of high precision gas flow standard device is needed to be established to meet the requirement of the value delivery.This project is devoted to the study of a gas flow standard device,which meets the requirements of flow standard device and supporting instrumentation fo the national calibration specification and verification regulation JJF 1357-2012 wet gas meter calibration standard and JJG1037-2008 Turbine flowmeter.This article mainly to complete the following aspects of the work:(1)Device structure design.The device comprises a standard metal tank,measuring tank,turbine flow meter,temperature sensor,pressure sensor,control system,data processing software and suitable pipeline.(2)Device control system design.This design includes hardware equipment selection,the realization of PLC as the next bit machine for data acquisition and signal output,using Visual Studio2010 Microsoft as the host computer to monitor the process of test and do data processing.(3)The uncertainty analysis of the device.The sources of uncertainty includes: standard metal tank,integrated temperature transmitter and pressure transmitter.In this article,a negative pressure drainage gas flow standard device was developed,and the overall expanded uncertainty was 0.10%(k=2).This device has the advantages of simple structure,convenient operation and easy maintenance,and is sure to improve the detection ability of the Tianjin institution of metrological supervision and testion.In the future of the measurement testing work,this device could service more and more production enterprises,research institutes of gas flow meter certification,calibration,type evaluation experiments and scientific research.