# Publications

### Oriol T. Valls

**Hydrodynamics of compressible superfluids in confined geometries**Abdul N Malmi-Kakkada, Oriol T Valls,Chandan Dasgupta,

*J. Phys. B 47, 055301 (2014)*
Download from http://arxiv.org/abs/1401.5683

**Abstract**

We present a study of the hydrodynamics of compressible
superfluids in confined geometries. We use a perturbative
procedure in terms of the dimensionless expansion parameter
$(v/v_s)^2$ where $v$ is the typical speed of the flow and $v_s$ the
speed of sound. A zero value of this parameter corresponds to the
incompressible limit. We apply the procedure to two specific
problems: the case of a trapped superfluid with a
gaussian profile of the local density, and that of a superfluid
confined in a
rotating obstructed cylinder. We find that the corrections due to finite
compressibility which are, as expected, negligible for liquid He, are
important but amenable to the perturbative treatment for
ultracold atomic systems.