2025, 2025) and Dymott et Al
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Rotation deeply impacts the construction and the evolution of stars. To construct coherent 1D or multi-D stellar structure and evolution fashions, we should systematically evaluate the turbulent transport of momentum and matter induced by hydrodynamical instabilities of radial and latitudinal differential rotation in stably stratified thermally diffusive stellar radiation zones. On this work, we investigate vertical shear instabilities in these areas. The complete Coriolis acceleration with the complete rotation vector at a basic latitude is taken under consideration. We formulate the problem by considering a canonical shear stream with a hyperbolic-tangent profile. We perform linear stability analysis on this base flow using each numerical and asymptotic Wentzel-Kramers-Brillouin-Jeffreys (WKBJ) methods. Two types of instabilities are identified and explored: inflectional instability, which occurs within the presence of an inflection level in shear flow, and inertial instability as a consequence of an imbalance between the centrifugal acceleration and stress gradient. Both instabilities are promoted as thermal diffusion turns into stronger or stratification turns into weaker.


Effects of the full Coriolis acceleration are discovered to be extra complex according to parametric investigations in huge ranges of colatitudes and rotation-to-shear and rotation-to-stratification ratios. Also, new prescriptions for the vertical eddy viscosity are derived to model the turbulent transport triggered by every instability. The rotation of stars deeply modifies their evolution (e.g. Maeder, 2009). Within the case of rapidly-rotating stars, such as early-sort stars (e.g. Royer et al., 2007) and younger late-kind stars (e.g. Gallet & Bouvier, 2015), the centrifugal acceleration modifies their hydrostatic construction (e.g. Espinosa Lara & Rieutord, 2013