TRANSPIRATION-INDUCED BUOYANCY EFFECT AROUND A HORIZONTAL CYLINDER EMBEDDED IN A POROUS-MEDIUM

Laminar free convection around a long porous limiting cylindrical surface arising from the buoyancy forces created by temperature as well as by transpiration-induced concentration gradients is investigated. All the fluid properties except for the temperature and concentration-dependent body forces are assumed to be constant. The dimensionless non-linear coupled boundary-layer equations embody the Prandtl number, the Schmidt number and the ratio of the concentration to the thermal buoyancy forces. Numerical results for the local Nusselt number, the local wall shear stress and the local Sherwood number are displayed graphically for the transpiration-induced convective diffusion of hydrogen, water vapor and naphthalene into an air-saturated porous medium. The dimensionless thermal, concentration and momentum boundary layer thicknesses, along with the cumulative tangential mass flow rate are given in tabular form. The analysis covers a wide range of blowing rates.