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Numerical hydrodynamic simulation of inviscid and viscous flows have shownthat significant outflows could be produced from the CENtrifugal pressuresupported BOundary Layer or CENBOL of an advective disk. However, this barrieris weakened in presence of viscosity, more so, if there are explicit energydissipations at the boundary layer itself. We study effects of viscosity andenergy dissipation theoretically on the outflow rate and show that as theviscosity or energy dissipation (or both) rises, the prospect of formation ofoutflows is greatly reduced, thereby verifying results obtained throughobservations and numerical simulations. Indeed, we find that in a dissipativeviscous flow, shocks in presence of outflows can be produced only if theShakura-Sunyaev viscosity parameter {\alpha} is less than 0.2. This is a directconsequence of modification of the Rankine-Hugoniot relation across the shockin a viscous flow, when the energy dissipation and mass loss in the form ofoutflows from the post-shock region are included. If we ignore the effects ofmass loss altogether, the standing dissipative shocks in viscous flows mayoccur only if {\alpha} < 0.27. These limits are tighter than the absolute limitof {\alpha} = 0.3 valid for a situation when the shock itself neitherdissipates energy nor any outflow is formed. We compute typical viscosityparameters required to understand spectral and temporal properties of severalblack hole candidates such as GX399-4, MAXI J1659-152 and MAXI J1836-194 andfind that required {\alpha} are indeed well within our prescribed limit.

Viscosity parameter in dissipative accretion flows with mass outflow around black holes