The hydrodynamic drag force in liquid helium at high Reynold's numbers

Abstract

The hydrodynamic drag force on a sphere falling in Helium I and Helium II at large Reynolds' Numbers was studied. It was found that for Reynolds' Numbers ~10 to the 6th the drag force can be adequately represented by the equation D=Co(1/2 pu2)A where P is the total density of the fluid, U is the velocity of the falling sphere, and A is the projected area of the sphere. In the region of Keynolds' Numbers studied in Helium II the superfluid and normal fluid appear to move together and turbulence in the superfluid seems to be present.