Visualization of two-phase interfacial structures in narrow channel

The gas-liquid interfacial structure of two-phase flow in narrow channel was measured by a novel measurement method using electrical conductance. This method consists of two different conductance measurements. One measure the conductance between neighbor electrodes on the sensor, and the liquid film thickness on the channel wall can be estimated from the measured conductance. Another measures the conductance between the opposing electrodes of two sensors which are installed on the walls of narrow rectangular channel. This conductance is related directly to void fraction in the narrow gap. These two measurements are performed simultaneously. Thus, two-dimensional distributions of both liquid film thickness and void fraction can be measured by using the liquid film sensors with numerous electrodes. The gas-liquid interfaces were reconstructed by estimating the thickness of the gaseous phase in the gap. From the reconstructed data, the void fraction and interfacial area concentration were obtained. (author)