FLOW OF THE POWER‐LAW FLUID IN THE INLET REGION OF A DUCT WITH BLOWING OR SUCTION

The hydrodynamic development of non‐Newtonian fluid flow in the entrance region of a duct with porous walls is examined numerically by solving the modified Navier‐Stokes equations. Cases involving blowing, suction, and no mass transfer through the walls are considered. Velocity distributions, pressure drops, and skin friction coefficients are presents for each case. A definite concavity is found in the velocity profile near the duct entrance for all cases. Results for Newtonian fluids are compared with previous studies in which boundary‐layer theory was used. In the region away from the entrance it is found that the present results are in good agreement with previous works. In the region close to the entrance, or in the case of suction, boundary‐layer theory is shown to be inappropriate.