Effects of surface mass transfer on steady mixed convection flow from vertical stretching sheet with variable wall temperature and concentration

Purpose - The purpose of this paper is to study the effects of surface mass transfer on the steady mixed convection flow from a vertical stretching sheet in a parallel free stream with variable wall temperature and concentration. Design/methodology/approach - An implicit finite difference scheme in combination with the quasilinearisation technique is employed to obtain non-similar solutions of the governing boundary layer equations for momentum, temperature and concentration fields. Findings - The numerical results are reported here to display the effects of mixed convection parameter, ratio of buoyancy forces, surface mass transfer (suction and injection), the ratio of free stream velocity to the composite reference velocity, Prandtl number and Schmidt number on velocity, temperature and concentration profiles as well as on skin friction, Nusselt number and Sherwood number. Research limitations/implications - Thermophysical properties of the fluid in the flow model are assumed to be constant except the density variations causing a body force term in the momentum equation. The Boussinesq approximation is invoked for the fluid properties to relate density changes, and to couple in this way the temperature and concentration fields to the flow field. The concentration of diffusing species is assumed to be very small in comparison with other chemical species far away fromthe surface. Hence the Soret andDufour effects are neglected.The stretching sheet is assumed to be subject to a power-law wall temperature as well as to a power-law wall concentration, in a parallel free stream. Practical implications - Convective heat and mass transfer over a vertical stretching sheet in a parallel stream is very important for various design of technological process are hot rolling, wire drawing, glass-fiber paper production, both metal and polymer sheets, for instance, in cooling of an infinite metallic plate in a cooling bath, the boundary layer along material handling conveyors, etc. Originality/value - The paper studies the combined effects of thermal and mass diffusion over a vertical stretching sheet with surface mass transfer.