Measurement of Void Fraction in a Two-Phase Flow for Unstable Liquid Conductivity in Multi-Electrode Voltage–Current System Using a Normalization Equation With Two Correction Parameters

The normalization equation with two correction parameters β and γ is proposed to estimate the void fraction of liquid-gas flow under the condition of unstable liquid conductivity using a multi-electrode voltage-current (me-VC) system. The variation of electrical current value due to change in liquid conductivity of liquid phase is corrected using parameter β. While γ is the gradient correction parameter, which corrects the different variation rate of normalized electrical current affected by liquid conductivity and the void fraction α in liquid-gas flow. A lookup table for β and γ is created based on the normalized electrical current obtained at four liquid conductivity and six void fraction conditions. From the experimental results, the proposed normalization equation with β and γ shows better performance in estimating void fraction than conventional normalization equation when the conductivity of liquid in liquid-gas flow is unstable. Through the results, it is found that the proposed normalization equation successfully measures the void fraction α within a 5% error rate.