The superfluid fraction will not rotate.
The simplest «experiment» is to watch as a container full of liquid helium suddenly springs a leak as it is cooled below the lambda point and the frictionless
superfluid fraction begins to pour through microscopic cracks that the normal liquid fraction can not enter.
Not exact matches
But stir the same helium like coffee and the normal liquid
fraction will resist the motion, imparting viscosity to the
superfluid mixture, after all.
But only the normal
fraction will rotate with the cylinder, because of friction between it and the cylinder walls; the
superfluid portion cuts right through the normal fluid and remains still.