steady viscous flow #3 flow in a circular pipe. steady viscous flow enters a tube from a reservoir.Wall friction causes a viscous layer, probably laminar to begin at the inlet and grow in thichness downstreampossibly becoming turbulent further inside the tube.-fully developed:the flow profile ceases to change with axial position and is said to be fully developed.Analytical difficulties arise if the duct diameter is tapered. Tapered flow does not becomes fully developed itself rather if the area increases with the flow direction, separation , backflow and unsteadiness complicate the flow pattern.(*subsonic diffuser*)->complex viscous flows: ->Properties of fluids:kinematic property transport propertyThermodynamics propertySurface tension, vaport pressure, eddy=diffusionsurface accomodation coefficents hedgingAccelaration of a fixed identity particle