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7.5 Applications of BLP 231

2.0 4.0 6.0 8.0
/
Fig. 7.5. The dimensionless velocity ' as a function of rj for various m.

"0 4 8 12 16 20

Fig. 7.6. The effect of mass transfer parameter f w on velocity profiles for m = 0.

suction and negative to blowing for zero pressure gradient. The effect of f w is
similar to that of the pressure-gradient parameter so that an increase in blowing
rate, like an increase in a positive ("adverse") pressure gradient, decreases the
slope of the velocity profile near the wall until it becomes zero at f w = —1.238.
With an increase in suction, as with an increase in a "favorable" (negative) pres-
sure gradient, the slope of the velocity profile increases. It is also seen from the
calculations that with an increase in suction, the effective transformed boundary
layer thickness becomes smaller, and with an increase in blowing, it becomes
bigger.

7.5.2 Nonsimilar Flows

To illustrate the calculation of nonsimilar flows with BLP, we consider a laminar
and turbulent flow over an ellipse and a NACA 0012 airfoil.

Calculations for an Ellipse
Consider an ellipse at zero angle of attack with its center at (a, 0), that is,