In district heating and cooling systems heated or chilled water is recirculated through a 10 to 20 km loop, exchanging heat with various installations. Much of the capital investment is concentrated in the pipes, pumps, and fittings needed for the recirculation. Drag reduction in turbulent flow could result in cost and energy savings. Several cationic and nonionic surfactant systems which form rod-shaped micelles have been identified as drag reducing agents. This research project will establish basic criteria for effective drag reducing systems and develop a convenient screening technique. Variables affecting micellar size, shape, and orientation will be studied, examining temperature, type and concentration of counter-ion, electrolyte content, and the effect of coadditives. Quasielastic light scattering will be used to study the micellar behavior of the additive systems. Interactive activities include teaching a course in the fundamentals of colloid science, participating in a university course which focuses on the unique problems of women and minorities in engineering and science, and contributing to a workshop for women in the College of Engineering. This project furthers VPW program objectives which are (1) to provide opportunities for women to advance their careers in engineering and in the disciplines of science supported by NSF and (2) to encourage women to pursue careers in science and engineering by providing greater visibility for women scientists and engineers employed in industry, government, and academic institutions. By encouraging the participation of women in science, it is a valuable investment in the Nation's future scientific vitality.
