BY : CHAM Development Team - M R Malin

FOR : Validation of Turbulence & Non-Newtonian Models

DATE : 1996 PHOENICS Version : 2.2.1

- The main objective of the calculations is to validate the low-Re
turbulence model and non-Newtonian model for the flow of Power-
Law fluids in pipes.
- Power-law fluids are time-independent viscous fluids for which
the shear stress is related to the deformation rate by the
consistency index K and the power-law index n. For n<1, the
fluid is pseudoplastic (shear thinning), and for n>1, it is
dilitant (shear thickening). If n=1, the fluid is Newtonian.
- The flow of Power-law in pipes is relevant in the many
engineering applications, especially within the manufacturing
and process industries.
- Calculations are made to calculate the frictional resistance,
along with the fully-developed velocity profile, for both
laminar and turbulent flow by use of the single-slab solver.
- The turbulence is represented by use of a modified version of
the Lam-Bremhorst low-Re k-e model.
- The parameters are: the Fanning friction factor f; the power-law
index n; and the Generalised Reynolds number:
Re=rho*{Wb**(2-n)}*{D**n}/({8**(n-1)}*{(0.75+0.25/n)**n}*K).

where K is the consistency, D is the pipe diameter, and Wb the bulk velocity.

2. LAMINAR FLOW: MEAN-VELOCITY PROFILES

3. TURBULENT FLOW: MEAN-VELOCITY PROFILES

4. TURBULENT FLOW: MEAN VELOCITY PROFILES

5. TURBULENT FLOW: LOGARITHMIC MEAN VELOCITY PROFILES

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