J. David et P. Filip, RELATIONSHIP OF ANNULAR AND PARALLEL-PLATE POISEUILLE FLOWS FOR POWER-LAW FLUIDS, Polymer-plastics technology and engineering, 34(6), 1995, pp. 947-960
This paper deals with both the axial and the tangential annular flows
of power-law fluids in concentric annuli, and it specifically focuses
on the relation volumetric flow rate Q against pressure drop P. Initia
lly the mutual compatibility of the hitherto obtained results is analy
zed, and from this, new results concerning behavior of a parameter lam
bda [a location of maximum axial (tangential) velocity component] are
derived. Then, approximative expressions for relations Q against P (in
dependent of lambda) are proposed in a sufficiently large region (kapp
a,n) where kappa represents annular aspect ratio and n the flow behavi
or index n. The deviations of these simple relations from the exact on
es are negligible.