Application of Soft Sensor in Dynamical Flow Measurement

The measurement of high frequency dynamical flow in dynamical test of electro-hydraulic propor- tional valve and electro-hydraulic servo valve is very difficult.This dissertation makes an attempt to apply the soft measurement theory in the measurement of high frequency dynamical flow.Basing on the laminar flow theory of fluid flow,the model of instantaneous flow in dynamic flow course was got.During the measure- ment,the differential pressure between two cross-cut sections along the pipe and the temperature of the fluid were measured online at first,then the instantaneous flow at any time can be calculated and output in computer through special program.In this way,the frequency range of the flow which can be measured is enlarged great- ly.