Void fraction measurement of dispersed bubbly flow with micro-bubbles by constant electric current method

Abstract

Void fraction is one of the dominant parameter of gas-liquid two-phase flow in industrial equipment. Impedance method based on the difference of electric conductivity and permittivity between liquid and gas can act as online measurements of the void fraction. However, existed methods are not applicable to dispersed bubbly flow because bubbles are dispersed in three dimensions. In the present study, Constant Electric Current Method available to the three dimensional dispersed bubbly flow with tiny bubbles (micro-bubbles) is developed. The proposed method is based polarization to estimate the void fraction from electrical signals. The method makes possible to measure the void fraction of the three dimensional dispersed bubbly flow. It is clarified that the present proposed measurement is applicable to measure the void fraction in bubbly flow more accurately than previous methods. © 2011 The Japan Society of Mechanical Engineers. © 2012 The Japan Society of Mechanical Engineers.