Flow and heating characteristics associated with heat transfer rates vis-a-vis entropy generation based on flow and thermal irreversibilities are numerically studied for thermal convection in the porous bed confined within various configurations of triangular enclosures. The triangular configurations involve various vertex angles ((Formula presented.) and (Formula presented.)) with three tilt positions (configurations 1–3) subjected to a linear heating pattern of the slanted walls. Numerical studies are carried out for various dimensionless parameters (Prm and Dam) at fixed Ram. Simulation results infer that the triangular configuration 3 [configuration 3: triangle is tilted perpendicularly from horizontal position (configuration 1 or 2)] involving (Formula presented.) is the optimal configuration based on the larger rate of heat transfer and moderate entropy production at larger porosities ((Formula presented.)) for buoyancy dominant scenarios ((Formula presented.)) irrespective of Prm. © 2022 Taylor & Francis Group, LLC.