Non-Newtonian fluid flow in an axisymmetric channel with porous wall

In the present article Optimal Homotopy Asymptotic Method(OHAM)is used to obtain the solutions of momentum and heat transfer equations of non-Newtonian fluid flow in an axisymmetric channel with porous wall for turbine cooling applications.Numerical method is used for validity of this analytical method and excellent agreement is observed between the solutions obtained from OHAM and numerical results.Trusting to this validity,effects of some other parameters are discussed.The results show that Nusselt number increases with increase of Reynolds number,Prandtl number and power law index.

Analytical investigation of laminar flow through expanding or contracting gaps with porous walls

Laminar,isothermal,incompressible and viscous flow in a rectangular domain bounded by two moving porous walls,w hich enable the fuid to enter or exit during successive expansions or contractions is investigated analytically using optimal homotopy asymptotic method(OHAM).OHAM is a powerful method for solving nonlinear problems without depending to the small parameter.The concept of this method is briefly introduced,and it's application for this problem is studied.Then,the results are compared with numerical results and the validity of these methods is shown.After this verification,we analyze the effects of some physical applicable parameters to show the efficiency of OHAM for this type of problems.Graphical results are presented to investigate the influence of the non-dimensional wall dilation rate(a)and pemeation Reynolds number(Re)on the velocity,normal pressure distribution and wall shear stress.The present problem for slowly expanding or contracting walls with weak permeability is a simple model for the transport of biological fuids through contracting or expanding vessels.