Research On Uncertainty Of Dynamic Pressure Testing System And Calibration Experiment Platform

In modern society,with the development of science and technology,from the Jiaolong to Tiangong-1,even from the high complexity of the industrial production to ordinary daily life,all aspects of people's life can not be separated from various types of pressure sensors.Pressure sensor is also one of the most popular sensor in the world.Therefore,when measuring transient pressure changes,the dynamic characteristics of pressure sensors are more and more important.This paper mainly studies the dynamic calibration system of pressure sensors.Firstly,the working principle of the pressure sensor and the dynamic indicators of pressure sensor is analyzed.In addition,the mathematical model of the dynamic characteristics of pressure sensor is established.The second part of this paper is to build a dynamic calibration system,which is composed of shock tube,high speed data acquisition system and a computer.The shock wave is applied to dynamically calibrate the pressure sensor.This part briefly introduces the high speed data acquisition module,discusses the data buffering mode and the interface of the high speed data acquisition system.Finally,the scheme of the high-speed data acquisition system is determined.The third part of this paper is the design of the high-speed data acquisition system,which includes two parts: speed module and acquisition module.The peripheral circuit includes signal processing part,high speed A/D converter part and USB transmission interface design part.This part realized the program design of the shock wave speed measurement system and the transient signal acquisition system of the pressure sensor.The logic timing control module of high speed A/D converter and the USB transmission interface is designed.At last,the concept of GUM&MCM is briefly introduced,and the uncertainty of this system is analyzed and calculated.And in order to verify the application of GUM,repeated experiments were done.And the uncertainty was calculated with GUM and MCM.By introducing the numerical tolerance,the results were verified and compared.