Velocity and surface force stress components

Consider the weighted residual statement of the equation of motion in a steady state Stokes flow model, expressed as 

FINITE ELEMENT MODELLING OF POLYMERIC FLOW PROCESSES 

BOUNDARY CONDITIONS IN POLYMER PROCESSING MODELS 95 Inlet conditions 

In general it is beneficial to use finer mesh divisions near a solid wall. 

In viscoelastic models in addition to the described conditions, stresses at the inlet should be given. As already mentioned there is no universal method to define such conditions, however, the following options may be considered (Tanner, 2000)  

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