Design of gas flow meter calibration based on sonic nozzles using negative pressure method

In order to improve the accuracy and efficiency of gas flow meter calibration, the auto gas meter calibration system using the negative pressure method based on automatic sonic nozzle was developed. Firstly the calibration principle of the sonic nozzle was analyzed, which is the base of the calibration. Then the overall system design and performance were given and the key issues and its solutions were discussed. Finally, the experimental data were acquired and analyzed. The calibration system which has been put into use in meter factory was proved to be automatic, high ability of anti-interference, exact, efficient and reliable during the applications.