An experimental and theoretical study of convection vertical concentric annulus two cylinders filling with porous medium was carried out . The experimental part was contained manufactured test rig and connected thermocouples then power on and reading temperatures until steady state . The theoretical part was contained solved governing equations by using Fluent software which drawing temperature profiles and stream functions for different ratio (r/R) and Ra . The results contained the relations between Nu with Ra and Nu with ratio (r/R) then experimental Nu with theoretical Nu so there was a good agreement between them.
