LAUSR

Abstract The fractional partial differential equations governing a mixed convective flow within an inclined wavy enclosure filled by a porous medium using hybrid nanofluids are presented. The forced flow is due to an inlet part in the bottom wavy wall as well as a vent is located at the top wavy surface. The Caputo definition is used to evaluate the time fractional derivatives and the Darcy model is applied for the porous medium. Cases of the mixed aiding and the mixed opposing flows are analyzed. The analysis is starting by mapping the complex geometry to a rectangular domain and the finite difference method is used to solve the transformed system. The present investigation is carried out for various values of order of the fractional derivatives (0.8 ≤ α ≤ 0.95), the amplitude of the wavy wall (0.85 ≤ A ≤ 0.95), the inclination angle 0 ≤ Φ ≤ π 2 , the Peclet number (1 ≤ Pe ≤ 20) and the Rayleigh number (10 ≤ Ra ≤ 103). The outcomes revealed that an increase in order of the fractional derivatives causes a reduction in the local and average Nusselt numbers. Also, the mixed convection as well as the Nusselt numbers are augmented as the amplitude of the wavy wall is grown.