Show simple item record

Elliptical instability of compressible flow and dissipation in rocky planets for strong tidal forcing

dc.contributor.advisorTilgner, Andreas Prof. Dr.
dc.contributor.authorClausen, Niels
dc.titleElliptical instability of compressible flow and dissipation in rocky planets for strong tidal forcingde
dc.contributor.refereeTilgner, Andreas Prof. Dr.
dc.subject.gokPhysik (PPN621336750)de
dc.description.abstractengThis thesis is divided into three main parts, in accordance with Chapters 2, 3 and 4. In the first part, Chap. 2, we investigate the elliptical instability. We calculate the growth rates of the elliptical instability under the influence of compressibility in a slightly elliptical deformed sphere. To do so, we solve the linearized Euler equations; the viscosity is included heuristically. The use of a power law for the radial dependence of the density and the anelastic approximation makes it possible to use semi-analytical methods to solve the equations. The influence of the orbital frequency of the perturber is considered. Exemplarily we apply the results to decide if elliptical instability is possible in the Earth perturbed by the Moon, Jupiter perturbed by Io and in the binary star system V636 Centauri. In Chap. 3 we present calculations of the tidal dissipation in rocky planets under strong tidal forcing. We estimate tidal dissipation by an equilibrium between heat transport and heat production due to tides. The influence of convection as opposed to melt migration as a possible heat transport mechanism is investigated, as well as dissipation in a homogeneous mantel as opposed to dissipation occurring mainly in the asthenosphere. We use Jupiter's moon Io and the exoplanet Corot-7b as objects of study. In Chap. 4 we solve the inviscid equations for inertial modes in shear flow, numerically for a profile with a velocity jump and analytically for a similar profile that has a continuous change of velocity instead of a jump. Our expectation is that with an appropriate steepness of the gradient in the continuous case, the flow profiles will approximately agree. We compare the resulting profiles to determine whether our expectation is
dc.contributor.coRefereeDreizler, Stefan Prof. Dr.
dc.subject.engtidal dissipationde
dc.subject.engplanets and satellitesde
dc.subject.engplanet-star interactionsde
dc.subject.enghydrodynamic instabilitiesde
dc.affiliation.instituteFakultät für Physikde

Files in this item


This item appears in the following Collection(s)

Show simple item record