Experimental study on the effect of high-molecular polymer as drag reducer on drag reduction rate of pipe flow

Abstract Three types of relatively high-molecular polymer were used to investigate drag reduction in single-phase flow through a horizontal, 12.7-mm pipe. Diesel oil and a mixture of diesel oil and model oil were employed as the oil phase. The effect of various factors on the drag reduction rate was investigated. These factors included the oil and drag reducer polymer type, polymer concentration, Reynolds number, temperature, and shear under turbulent flow (Reynolds number: 3000–12000). The experimental results indicated that the drag reduction rate increases initially (when the polymer concentration increases from 1 ppm to 4 ppm) and then stabilizes at some maximum value. The maximum rate occurred at the maximum concentration (i.e., 5 ppm) in the experiment considering the diameter of the pipeline. The experimental results also indicated that, for a given concentration of a given drag reducer, the drag reduction rate differs with the type of oil system. Similarly, for a given oil system with a given concentration, the reduction rate varied with the type of drag reducer. In addition, the Reynolds number and shear have a significant effect on the drag reduction rate, but the effect of oil temperature can be ignored.