  Could tidal dissipation within Enceladus' subsurface ocean account for the
observed heat flow? Earthlike models of dynamical tides give no definitive
answer because they neglect the influence of the crust. I propose here the
first model of dissipative tides in a subsurface ocean, by combining the
Laplace Tidal Equations with the membrane approach. For the first time, it is
possible to compute tidal dissipation rates within the crust, ocean, and mantle
in one go. I show that oceanic dissipation is strongly reduced by the crustal
constraint, and thus contributes little to Enceladus' present heat budget.
Tidal resonances could have played a role in a forming or freezing ocean less
than 100 m deep. The model is general: it applies to all icy satellites with a
thin crust and a shallow ocean. Scaling rules relate the resonances and
dissipation rate of a subsurface ocean to the ones of a surface ocean. If the
ocean has low viscosity, the westward obliquity tide does not move the crust.
Therefore, crustal dissipation due to dynamical obliquity tides can differ from
the static prediction by up to a factor of two.
