Signal Processing method in using four-sensor probe for measuring the velocity vector of air-liquid two phase flow

This paper describes a new design of a local four-sensor probe which was used to measure the local velocity vector of the dispersed phase in a bubbly gas-liquid two phase flow. Based on the four-sensor probe signals, a new signal processing technique was also introduced. Reference data was obtained using high speed cameras to determine the optimum value for the threshold voltages relevant to the output signals from the four sensors on the probe. Groups of signals from the four sensors that were generated by the same bubble were identified but the signals from some bubbles were ignored by the signal processing scheme. After using the signal processing technique, the results have been improved compared with the results without the signal processing technique.