Mechanical and thermal characteristics of a mixed convection boundary-layer flow in a saturated porous medium

The mixed convection over a vertical surface adjacent to a fluid saturated porous medium and having the temperature distribution Tw(x) = T∞ + T0 · (x/L)λ is considered in the boundary-layer and Boussinesq approximation for the value λ = −1/3 of the power-law exponent. It is shown that in the whole range −∞ < ε < +∞ of the mixed convection parameter ε an infinite number of solutions exist which are associated with different values of the dimensionless wall temperature gradient θ′(0) ≡ h. These solutions are investigated analytically and numerically in detail. The effect of a thermodynamic requirement on the existence domain of the physical solutions is discussed in the context of results reported by other authors.