Non-newtonian fluid flow in axisymmetric sudden expansion

In this paper، the steady flow of non newtonian fluid in axisymmetric sudden expansion with ratio 1:3 solved numerically. Finite difference method is used to discrete the governing equation on the staggered mesh. The non-newtonian model that used is the Carreau Yasuda five constants viscometric model. Using this model، non newtonian properties of the fluid can be simulated well. The range of the power law index is considered between 0. 6 and 1. 0. The results of this paper include the streamline diagrams، the axial velocity، viscosity and stress profiles for different values of the non newtonian property. These results show that length of vortex and fully developing region decreases، the pressure loss and the maximum axial velocity increases when the power law index (n) is decreases. It is shown that the magnitude of the velocity and viscosity in the center of the vortex are minimum and maximum respectively.