Heat transfer from a 5-by-4 array of protruding heat sources in the bottom wall of an adiabatic enclosure is investigated experimentally and numerically. The enclosure has a fixed inlet and different outlets. Flow velocity and applied heat fluxes are varied. Steady-state temperatures of the heat sources, air inlet and outlet temperatures, and enclosure wall temperature are measured. Results indicate that the first row is the coolest, and the Nusselt numbers of the heat sources, which are near the enclosure wall, are higher than those in the inner side. There is a good agreement between the experimental and numerical results.