Abstract��
In this paper,the drag reduction behavior of a surfactant-counterion mixture is investigated.The experimental apparatus is closed circular system with 16mm pipe diameter,the experimental flow regime is turbulent with Reynolds number 10 4��5��10 4,the results show that,the mixture of cationic surfactant C n TAC( n =16,18)and counterion sodium salicylate NaSal is a very good drag reducing additive,the drag reduction increases with increasing C n TAC( n =16,18)/NaSal concentration,there is maximum effective temperature for drag reduction within a certain velocity region,the maximum effective temperature increases with increasing velocity,The optimum mass ratio of NaSal to C n ATC( n =16,18)for drag reduction is 1��1,the length of chain and flexibility of rod-like micellar may be the main factors to determine the optimum ratio.Inorganic electrolyte sodium chloride NaCl has great effect on drag reduction of C n TAC/NaSal system,the drag reduction increases with increasing NaCl concentration,C n TAC( n =16,18)/NaSal with higer concentration NaCl may be a potential practical drag reducing additive.
1999, Vol. 16 
