Void fraction measurement using a laser beam

Void fraction is an important factor for determining gas-liquid mixture flow in pipes and columns. There are many methods to measure the void fraction such as, electrical probe, capacitance, Auto-transformer, thermal anemometry, radioactive absorption and scattering, and optical methods. The present method is an optical arrangement, which is based on using He-Ne laser source and a proper detector. The detector is positioned diametrically on the opposite side of the laser source. The void fraction has been measured by finding the attenuation of laser beam power during its passage through the bubble - liquid mixture. The experimental results revealed the viability of measuring void fraction using laser transmission through fluid mixture.