A model for winds from galactic disks

A hydrodynamic model is constructed to represent a wind originating in the disk of a spiral galaxy. The gas flow is assumed to be steady, nondissipative, axisymmetric, and (to simplify the calculations) self-similar, scaling in radius. Various heating processes are represented by a pressure-density relation which is isothermal near the disk and adiabatic far from the disk. Wind solutions are found for a range of values of initial parameters in the disk. In a regime where the self-similarity might be expected to be valid, scaling parameters can be chosen which are reasonable for a large spiral galaxy with a hot, tenuous corona.