The conversion and selectivity of an extremely large multi-tubular fixed-bed reactor of industrial level remarkably relate to the distribution homogeneity of temperature and flow of heat transfer medium in shell side. In this work

through introducing two items of resistance source and a dispersed heat transfer source

the distribution of temperature and flow in the shell of a multi-tubular fixed-bed reactor of industrial level for butane oxidation to maleic anhydride was investigated by CFD simulation. Subsequently

effects of the window size and the location of baffles on the pressure drop of shell side and the distribution of temperature and flow were studied. It showed that the pressure drop of the shell side achieved by simulation are in good agreement with that by calculation of experimental equations

and the simulated temperature distribution of shell side is in accordance with industrial experimental data. With an increase in window area of the baffles

the pressure drop of shell side exponentially decreased

the range of large temperature difference (with a radial temperature difference greater than 2 K)

and the radial temperature difference increased. With a decrease in height of the first baffle

both the range of large temperature difference and the radial temperature difference reduced

while the pressure drop of shell side did not show any consistent changes. Here the modeling strategy can be a good way to optimize the design of extremely large multi-tubular fixed-bed reactor of industrial level.