Abstract
This report describes flow properties of surfactant aqueous solutions in pipe junction with dividing angle of 90 degrees. Ethquard was used as surfactant and its concentration was 100ppm. Energy losses due to dividing flow and pipe friction losses before and behind junction were measured. The pipe friction factors before and behind the junction decreased than those for water. However, the drag reduction and behind the junction were less than before it. The critical Reynolds number (Re_c) also decreased. The dividing loss coefficients became large than in the water at Reynolds number under Re_c and agreed with those for water at beyond Re_c.
