Effect of fluid velocity, temperature, and concentration of non-ionic surfactants on drag reduction

The drag reduction (DR) and heat transfer efficiency reduction (ER) of non-ionic surfactant as a function of fluid velocity, temperature, and surfactant concentration were investigated. Several types of new surfactants, which contain amine-oxide and betaine, were developed. An experimental apparatus consisting of two temperature controlled water storage tanks, pumps, test specimen pipe and the piping network, two flow meters, two pressure gauges, a heat exchanger, and data logging system was built. From the experimental results, it was concluded that existing alkyl ammonium surfactant (CTAC; cethyl trimethyl ammonium chloride) had DR of 0.6–0.8 at 1000–2000 ppm concentration with fluid temperature ranging between 50 and 60 °C. However, the DR was very low when the fluid temperature was 70–80 °C. The new amine oxide and betaine surfactant (SAOB; stearyl amine oxide + betaine) had lower DR at fluid temperatures ranging between 50 and 60 °C compared with CTAC. However, with fluid temperature ranging between 70 and 80 °C the DR was 0.6–0.8 when the concentration level was between 1000 and 2000 ppm.