A SYSTEM OF DATA ACQUISITON AND PROCESSING IN AEROENGINE

A comprehensive system of data acquisition and processing in aeroengine testing is described which can acquire and process all parameters including dynamic ones. Its advanced hardware and program compiled with PL/M language enhance its maximum acquisition speed to more than 5000 times per second. The thermocouple regression equations are obtained by polynomial fitting in sections with changing weight and applied to linearization of temperature measurement. The self-made sca-nivalve controlled by microcomputer is used for steady multipoint pressure measurement, and the technique of real time calibration is also adopted to guarantee high accuracy of the measurement. The self-made frequency channel is capable of turning frequency into analog or digital signal in real time and its response time makes up only one period of the signal measured.The practice of employing this system in aeroengine testing shows that its hardware and software are reliable and easy to operate. The time of the whole processingreduces from half a day manually to merely several minutes. The test run time is also saved up to about 20%, but the average measurement accuracy increases from 0.8% to 0.3%.