Drag reduction in two-phase annular flow of air and water in an inclined pipeline

Abstract

Measurements of drag reduction for air and water flowing in an inclined 0.0127 m diameter pipe were conducted. The fluids had an annular configuration. The injection of drag reducing polymers (DRP) solution produced drag reductions as high as 71% with a concentration of 100 ppm in the pipeline. A maximum drag reduction that is accompanied (in most cases) by a change to a stratified or annular stratified pattern. The drag reduction is sensitive to the gas and liquid superficial velocities and the pipe inclination. Maximum drag reduction was achieved in the case of pipe inclination of 1.28 o at the lowest superficial gas velocity and the highest superficial liquid velocity.