Turbulent Drag Reduction Efficiency and Mechanical Degradation of Poly(Acrylamide).

Turbulent drag reduction (DR) efficiency and mechanical degradation of high-molecular-weight poly(acrylamide) (PAAM) was investigated in a rotating disk apparatus. Drag reduction efficiency of PAAM was measured as a function of rotational speed, polymer concentration, and temperature and then compared with that of poly(ethylene oxide) (PEO). The PAAM exhibited relatively high shear resistance, and its mechanical degradation behavior in a turbulent flow was examined by using both an exponential and a fractional exponential decay equation. [ABSTRACT FROM AUTHOR]