An effect of the side-tube configuration on the void fraction measurement

The development of a practical and simple on-line void fraction measurement of two-phase pow is of prime interest in applications for nuclear reactor safety research and chemical engineering plants. Experiments were performed at a system pressure of I arm. The test sections were made of transparent vertical acrylic pipe with three inner diameters of 1.9, 2, and 2.54 cm. The void fraction was measured by different sizes of side tubes in an air-water two-phase flow, and the void fraction was also compared with the data, which were measured from the liquid holdup between two quick-close valves. The experiment results showed a good agreement for void fractions <0.3, bur the error could be large when the pow was in the slug regime.