AbstractThe effects of chemical reactions on wall heat transfer coefficients in packed bed reactors operating at equilibrium or near equilibrium conditions are explored by means of one‐dimensional and two‐dimensional models. Both approaches suggest using Damköhler number or ratios of reacting to frozen heat capacity as parameters in heat transfer correlations. Available data for the methane‐steam reforming reactors were used to establish a suitable correlation for use in thermal design of reacting beds of solids, i. e. NNu= 0.195 NRe0.8exp. (0.21 σ)This correlation can be applied with reasonable accuracy for beds which are 3 to 5‐in. in diameter and bed to particle diameter ratios from 5 to 10. A review of available correlations for wall coefficients obtained under non‐reacting packed bed conditions is als