The influence of dilute SLS solution on drag-reduction

The aim of this research is to study the effect of Sodium Lauryl Sulfate (SLS) on the turbulent water flow inside a horizontal pipe. An experimental apparatus was designed and built, which consist of a reservoir tank, manometer, flow meter, gear pump, horizontal pipes. SLS was added different concentration (100, 200, and 300 ppm) to tap water to flow through 31.75 mm pipe diameter at different flow rate (2.0, 3.0, 4.0, 5.0, and 6.0) m³/hr. The drag-reduction percentage (Dr %) was calculated for all concentration at different rates. The maximum drag-reduction at 300 ppm concentration and 6.0 m³/hr flow rate was (21.352%). And the frictional factor (f) at the same condition was 3.88*10^-3. Percentage flow increase (TI %) was calculated for all conditions and the maximum result was (14.123 %) at the same conditions above. The results indicated that the increasing of concentration and flow rate lead to rising drag-reduction percentage and percentage flow increase. About friction factor most of the experimental data points are located at or close Blasius asymptote, which give an indication that the starting points of the operation are close to that of the standard operation conditions suggested in the literatures.