Experimental Investigation on Drag Reduction of Mixed Peo and Ctac/Nasal Aqueous Solution in a Rotating Disk Apparatus

Abstract

Drag reduction (DR) by the additive of mixed surfactant and polymer is investigated in detail in a rotating disk apparatus (RDA). Polyethylene oxide (PEO) and Cetyltrimethyl ammonium chloride (CTAC)/sodium salicylate (NaSal) are chosen as polymer and surfactant, respectively. It is investigated on the influence of combination concentration of polymer & surfactant, temperature and Reynolds number on the drag-reducing rate. The present experimental results show that the drag-reducing rate of the mixed solution is definitely higher than that of the pure PEO or CTAC/NaSal solutions. This phenomenon is especially sharp at the high temperature and/or the large Reynolds number. When the temperature is higher than 30℃, the net enhancement of DR is the sharpest for the mixed solutions of any CTAC/NaSal concentration and 30 ppm PEO. However, for the mixed solutions of the fixed PEO concentration, the combination concentration of PEO & CTAC/NaSal, which causes the sharpest enhancement of the DR, depends on temperature. In short, comparing with the only addition of PEO or CTAC/NaSal, the coupled addition of PEO & CTAC/NaSal can obtain the very good drag-reducing effect for the rotating disk apparatus at the high temperature and/or the great Reynolds number.