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In this study forced convection heat transfer in a pebble bed cylindrical channel with internal heat generation was investigated experimentally. Dry air has been used as working fluid in heated spheres cooling process. Internal heating was generated uniformly, by electromagnetic induction heating method in a metallic spheres which have been used in test section. Spheres are made of stainless steel and their diameter is in the range of 5.5-7.5 mm. Present study was performed at steady state and turbulence flow regime, with Re number in the range of 4500-9500. Different parameters resulted by variation of spheres diameter, flow velocity and generated heat on forced convection heat transfer was studied. According to thermal and hydrodynamics studies, it can be said as Re number increases, heat transfer coefficient will increase. Also heat transfer coefficient has been increased by spheres diameter decrement. The generated heat has a little influence on heat transfer coefficient. The effect of pressure variations on forced convection heat transfer can be neglected. Porous channel has greater friction factor in comparison with an empty channel. The friction factor in empty channel is always less than 1 but for porous channel this parameter is in the range of 10-25.