A REEVALUATION OF FLUID-FLOW, HEAT-TRANSFER AND CHEMICAL-REACTION IN CATALYST FILLED TUBES

The problem of heat transfer through the wall in catalyst filled tubes with a tube to particle diameter ratio greater than 4 divided-by 5 and industrial flow rates with and without chemical reaction has been reevaluated through detailed experiments and model calculations. The results confirm and extend findings of Vortmeyer et al. that reaction and heat transfer can only be modeled with independently determined parameters if the radial variation of the axial mass flow velocity is properly considered. In this case the wall beat transfer coefficient h(w) and the effective conductivity lambda(r) are independent of lenght and have values about 20 to 40 % lower than those obtained from available correlations that are based upon plug flow.