Measurement of bubble/slug velocity and size in vertical pipe based on optical cross-correlation method

Based on the principle of the cross-correlation, the method for measuring the velocity and size of bubbles in transparent gas-liquid two-phase flow in a vertical pipe is proposed by taking optical attenuation signal as the object. This method is used to measure the bubble velocity and size of transparent gas-liquid two-phase flow in vertical pipeline of two-phase flow experimental platform, and compared with synchronous measurement by image method. The experimental results show that the relative deviation of velocity and size between optical cross-correlation measurement and image method is less than 3% and 5%, respectively. The optical cross-correlation method can be used to measure the bubble velocity and size parameters of transparent gas-liquid two-phase flow in the vertical pipe without contact, and this method is suitable for industrial applications.