Water Soluble Polymers as a Means to Increase Flow Capacity: Field Experiment of Drag Reduction by Polymer Additives in an Irrigation Canal

Abstract

A drag reduction method by polymer additives was tested for the first time in a large scale open-channel watercourse. Ten and a half tons of a water soluble polymer were injected during 15 consecutive hours in the upstream section of an irrigation canal in steady state, leading to a 20 ppm concentration of polymer in the water. The evolution of the water depth was measured every 10 min for 18 h along ten sections further downstream, up to a distance of 26.3 km from the injection section. The water depth at all sections remained constant until the arrival of the polymer, at which time it strongly decreased, sometimes with a slight water-depth increase beforehand; the depth then remained constant as long as the polymer injection remained. A maximum water depth reduction of 26 cm (i.e., 17%) was measured at the first cross section (2 km downstream from injection). The water depth reduction decreased to 10% and 3% at 10 and 20 km downstream from the injection, respectively. However, further downstream, at a distance of 26.3 km, the water depth increased by 5%. This paper also discusses the environmental impacts of polymer injection through analysis of samples taken from the water and bed material before and during the experiments.

Spotlight on the Life Cycle of Acrylamide-Based Polymers Supporting Reductions in Environmental Footprint: Review and Recent Advances

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Effect of Water on Flow Fluctuation in River Flow

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Critical Role of Ionic Properties on the Turbulence Drag Reduction Performance of Various Polyacrylamide Polymers in Liquid

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