Laminar semi-porous channel electrically conducting flow under magnetic field

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.

Laminar electrically conducting fluid flow in various conduits under different magnetic fields has received great attention in recent years due to its various applications for biomedical (i.e.: blood filtration in artificial kidney), thermal (i.e.: cooling of turbine blades), chemical (i.e.: food processing), environmental (i.e.: dust separation) and nuclear (i.e.: ionization control) purposes. Present paper studies flow characteristics of electrically conducting fluid under uniform magnetic field in the small gap between uniformly moving lower plate and a fixed parallel semi porous plate that governed by dimensionless Hartman number (Ha), and Reynolds number (Re). The weighted residual Least Squares Method (L.S.M.) is used to solve the two dimensional governing simulation equations. In the range Re < 1.0 and Ha < 1.0, neither Ha nor Re has noticeable effect on vertical flow velocity V. The rate of V is linear within the gap and vanishes in the vicinity of both plates. Fluid flow rate q leaving out through the semi porous upper plate shows significant dependency on both Ha and Re, where it decreases with increasing either Ha or Re due to the dependency of the horizontal velocity U on both Ha, and Re. In the ranges 1.0 < Re, Ha < 10 both Ha and Re also still have minor effects on V. At higher Re the results show higher shear stress and lower U values in vicinity of lower plate, signifying a reluctant fluid flow that does not follow the speeding up of the moving lower plate. At Ha = 10, the effect of Re on U diminishes to its lowest limit, and the flow suffers an almost oscillating nature in the upper 75% of the gap between the plates, and a very high shear stress is in the lower 25% of the gap. Present results agree well with other published results that had used Galerkin method, numerical methods and Homotopy analysis method.