Abstract :
In this paper consideration is given to viscose, incompressible, time-depended and non-Newtonian fluid flowing in a straight pipe with square cross-section under the action of pressure gradient. In particular consideration is given to second order fluid flow which can be represented by the equation of state of the form: Tij = 2ƞeij + 4 varsigma sum 2 k=1 eik ejk i,j= 1,2 Where η viscosity coefficient and ζ is normal stress coefficient and, Tij and eij , i,j =1,2 are the stress and rate of strain respectively. Cartesian coordinate system has been used to describe the fluid motion and it is found that equations of motion are controlled by Reynolds number and non-Newtonian parameter. The motion equations are solved by an explicit method namely MAC. Our study is ended with studying the effect of Reynolds number and non-Newtonian parameter on the fluid flow.