Rotating disk apparatus for polymer-induced turbulent drag reduction

다국어 초록 (Multilingual Abstract)

In order to investigate turbulent drag reduction (DR), a rotating disk apparatus (RDA) generating an “external flow”

was designed and then polymer-induced DR efficiency of water-soluble polymers both poly (ethylene oxide) (PEO)

and poly (acryl amide) (PAAM) were examined as a function of either polymer concentration or temperature. The need

for a sensitive measuring system at high Reynolds numbers has stimulated the development of a high-precision computer-

aided system, which is able to measure the difference between the torques for a Newtonian fluid and a dilute

polymeric solution with drag reducers very accurately. Their mechanical degradation behavior in the RDA as a function

of time in a turbulent flow was also analyzed using both a simple exponential decay function and a fractional exponential

decay equation. The fractional exponential decay equation was found to fit the experimental data better than

the simple first-order degradation exponential decay function in the case of PEO.

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