Abstract
We measured pressure drops and investigated flow properties of water and dilute aqueous polymer solutions of polyacrylamide (PAA) in capillary flows with bend section. Capillary sizes used as 125 μm and 410 μm. For PAA, dilute concentrations were used (in the range from 1 ppm to 100 ppm). For comparison, straight capillaries were investigated. Agreement between the water results and the predictions of laminar flow or Blasius expression was obtained, and pseudo-laminarization of PAA was suggested. Moreover, pressure drop increases were observed by bend section. However, pressure drop decreases were measured by using PAA. Thus, drag reduction for dilute polymer solutions was strongly suggested in capillary flows with bend section.
