Containing liquid helium in it's superfluid state is of course known to be problematic. Escape by crawling up container walls to 'leak' through solid containers and similar difficulties being a concern.

How would superfluid helium respond to an ultrasonic barrier reinforcing the surface of a container, or perhaps simply a vibrating container?

In a broader statement of the question, I am curious of superfluid response, if any, to kinetic energy in the system. I have in general wondered, do the waves even interact without a fluid being viscous?


Sound is a compression wave not a shear wave, so the viscosity of the liquid has no (direct) effect on it. The speed of sound in a liquid is given by:

$$ v = \sqrt{\frac{K}{\rho}} $$

where $K$ is the bulk modulus and $\rho$ is the density. The viscosity does not appear in this equation.

A quick Google found data on the speed of sound in liquid helium in this book. Figure 41 from the book shows:

Speed of sound in liquid helium

Apart from the dip at the $\lambda$-point there is nothing remarkable about this curve.

The point of all this is that there is no reason to suppose ultrasound would have any unusual effect on the flow of superfluid helium.


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