THE ONION VORTEX - AN ADIABATIC, STEADY-STATE FLOW OF A PERFECT GAS IN THE INFINITE DOMAIN

This Brief Communication gives a new exact solution of the nonlinear adiabatic equations of fluid flow for a perfect gas in the infinite three-dimensional domain that is not the trivial constant flow. The temperature of the gas is an arbitrary function of the radius. The velocity of the gas can be described by considering concentric spheres, one for each value of the radius, which rotate about the same fixed axis through the common center of the spheres, the angular velocity of each sphere being dependent upon the temperature at the radius. The velocity of the gas at a point is then that of the sphere at that point. The nature of this flow suggests that it be named an "onion vortex." It is shown that onion vortices for the same temperature distribution have an additive property, which is surprising in the context of nonlinear equations.