A Note On The Inhibition Of Cavitation In Dilute Polymer Solutions

Cavitation inception was investigated on a series of hemispherical nosed bodies rangine in diameter from 6.3 mm (1/4 inch) to 203.2 mm (8 inches) in both pure water and dilute aqueous polymer solutions. The desinent value of cavitation index is reduced by as much as 50% on the smaller bodies but the polymer effect is almost negligible on the largest body. There is strong evidence that the favorable effect of polymer addition is due to a reorientation of the flow field near a laminar separation bubble. It is further noted that the effect is probably limited to Reynolds numbers typical of laboratory experiments and would not exist at full scale conditions.