Maple and spectral computation of free convection slip mass transfer from a spinning conical porous body to an anisotropic permeable medium

Many industrial materials processing and mechanical engineering systems feature swirl flows from rotating bodies including thin film coatings, centrifugal separation and mixing devices. This work therefore explores the steady axisymmetric laminar boundary layer natural convection mass transfer from a spinning porous vertical conical geometry in anisotropic high permeability porous media. Slip effects are incorporated at the cone surface. The transformed boundary value problem is solved subject to prescribed surface and free stream boundary conditions with a MAPLE 17 shooting method. Validation with a Chebyshev spectral collocation method is included. The influence of tangential Darcy number, swirl Darcy number, Schmidt number, rotational parameter, momentum (velocity slip), mass slip and wall mass flux (transpiration) on the velocity and concentration distributions is evaluated in detail. The computations show that tangential and swirl velocities are enhanced generally with increasing permeability functions (i.e. Darcy parameters). Increasing spin velocity of the cone accelerates the tangential flow whereas it retards the swirl flow. An elevation in wall suction depresses both tangential and swirl flow. However, increasing injection generates acceleration in the tangential and swirl flow. With greater momentum (hydrodynamic) slip, both tangential and swirl flows are accelerated. Concentration values and Sherwood number function values are also enhanced with momentum slip, although this is only achieved for the case of wall injection. A substantial suppression in tangential velocity is induced with higher mass (solutal) slip effect for any value of injection parameter. Concentration is also depressed at the wall (cone surface) with an increase in mass slip parameter, irrespective of whether injection or suction is present.