## THERMAL SCIENCE

International Scientific Journal

### EFFECT OF VARIABLE VISCOSITY AND SUCTION/INJECTION ON THERMAL BOUNDARY LAYER OF A NON-NEWTONIAN POWER-LAW FLUIDS PAST A POWER-LAW STRETCHED SURFACE

**ABSTRACT**

The analysis of laminar boundary layer flow and heat transfer of non-Newtonian fluids over a continuous stretched surface with suction or injection has been presented. The velocity and temperature of the sheet were assumed to vary in a power-law form, that is u = U0xm, and Tw(x)=T4+Cxb. The viscosity of the fluid is assumed to be inverse linear function of temperature. The resulting governing boundary-layer equations are highly non-linear and coupled form of partial differential equations and they have been solved numerically by using the Runge-Kutta method and Shooting technique. Velocity and temperature distributions as well as the Nusselt number where studied for two thermal boundary conditions: uniform surface temperature (b = 0) and cooled surface temperature (b = -1), for different parameters: variable viscosity parameter θ, temperature exponent b, blowing parameter d and Prandtl number. The obtained results show that the flow and heat transfer characteristics are significantly influenced by these parameters.

**KEYWORDS**

PAPER SUBMITTED: 2009-07-13

PAPER REVISED: 2009-07-24

PAPER ACCEPTED: 2009-11-19

**THERMAL SCIENCE** YEAR

**2010**, VOLUME

**14**, ISSUE

**Issue 4**, PAGES [1111 - 1120]

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