Two heat transfer parameters

the radial effective conductivity ker and the wall heat transfer coefficient hw were estimated by means of non-linear least square. The two-dimensional pseudohomogeneous model was solved by using orthogonal collocation. A fixed bed packed with vanadium-phosphorous catalyst for oxidation of n-butane to maleic anhydride was studied. The temperatures at forty collocation points along the radial direction were measured by a multi-channel potential logger. The effects of bed height

particle Reynolds number

tube diameter to particle diameter ratio

and wall temperature on kei

and hw were investigated

and the following correlations were proposed (5.5