Effect of Pressure on the Wave Behavior in Horizontal Wet-gas Annular Flow

Interfacial disturbance waves play a very important role in the mass, momentum and energy transport phenomena and modeling of gas-to-liquid momentum transfer and liquid film behavior in annular flow. The disturbance waves are not only the major source of entrained droplets, but also act as a roughness to the central gas flow and contribute to the frictional pressure drop in annular flow. In spite of their importance, majority of the experimental data available in literature on wave properties (wave velocity, wave frequency and wave spacing) are limited to near atmospheric conditions. In view of this, based on NIR technology, horizontal wet-gas annular flow is investigated by theoretical analysis and experimental verification in 50mm inner pipe diameter at five pressures $(0.1 \sim 0.5$ MPa). Total 35 points under 7 groups flow conditions are selected for qualitative and quantitative research. By data analysis of wave velocity and wave frequency and the light signals analyses of probability density function and wavelet energy, the effect of pressure on the wave behavior is preliminary investigated and discussed.