  Convection-dominated accretion flow (CDAF) is a promising model to explain
underluminous accreting black holes in X-ray binaries and galactic nuclei. I
discuss effects of angular momentum transport in viscous hydrodynamical and MHD
CDAFs. In hydrodynamical CDAFs, convection transports angular momentum inward,
and this together with outward convection transport of thermal energy determine
the radial structure of the flow. In MHD CDAFs, convection can transport
angular momentum either inward or outward, depending on properties of
turbulence in rotating magnetized plasma, which are not fully understood yet.
Direction of convection angular momentum transport can affect the law of
rotation of MHD CDAFs.
