Instantaneous differential pressure signals of oil-gas-water multiphase flo
w in a horizontal pipe are measured with a piezo-resistance differential pr
essure transducer with fast response. The signals are denoised by using wav
elet theory and then the characteristic vectors of various flow regimes are
obtained from the denoised differential pressure signals with fractal theo
ry. The characteristic vectors of known flow regimes are fed into a neural
network for training and later on weight coefficients of neural network are
obtained through training. Then, the characteristic vector of some kind of
unknown flow regime of oil-gas-water multiphase flow is fed into the neura
l network and the neural network can automatically send out the information
in respect to the classification of flow regime, thus the intelligent iden
tification of flow regime of oil-gas-water multiphase flow is realized. Pra
ctice shows that this new method for identifying flow regimes of multiphase
flow and the system constructed with the method has the merits of high acc
uracy, fast response and automatic identification without artificial interv
ention etc. It will have promising application prospect. (C) 2001 Elsevier
Science Ltd. All rights reserved.