ADVECTION-DOMINATED OUTFLOWS

We obtained self-similar solutions for rotating advection-dominated (n o radiative cooling) hydrodynamical bipolar outflows without the prese nce of a magnetic field. These solutions are two-dimensional and can h ave arbitrary power-law scaling with radius. The outflow is driven by the pressure, the centrifugal force, and the viscous diffusion, which also transports angular momentum outward. Depending on the density dis tribution as well as the radial velocity near the equatorial plane of the flow, two types of outflows are found: accretion outflow and eject ion outflow. The viscosity parameter (alpha) affects the outflow in a complicated way, but, in general, high viscosity helps to generate bip olar outflow. Our solutions encompass previously studied cases.