EFFECTS OF A DRAG-REDUCING POLYMER ON THE TURBULENT BOUNDARY LAYER.

Data is presented showing the time effects caused by polymer solution drag-reduction degradation on the mean velocity and axial fluctuating velocity profiles. Velocity profiles obtained in the study at high drag reduction using a time-study technique demonstrate that the polymer molecules affect not only the near wall region, as shown by the change in viscous sublayer velocity gradient and sublayer thickness, but that the turbulent core is effected as well, as evidenced by the fact that the slope of the turbulent core velocity profile differs substantially from the Newtonian value of 5. 75.