Multiphase pipe flow velocity profile measurements by Doppler ultrasound containing a high level of colored noise

This paper presents an application of continuous wave Doppler ultrasound measurement to two phase flow in pipes. A specific Doppler system has been developed for this purpose. The presence of strong colored noise in the experimental Doppler signals was an incentive to use a complex UDV^H factored form of the instrumental variable identification technique. Direct Doppler frequency estimation is then obtained using the argument poles of the autoregressive model which identifies the Doppler part of the signal. The performed tests with a complex parametric theoretical model, simulated and experimental Doppler signals have demonstrated the superiority of this adaptive signal processing method compared with the UDU^H factored form of the recursive least square autoregressive identification algorithm