Industrial & Engineering Chemistry Research, Vol.47, No.8, 2656-2665, 2008
A computational transport model for wall-cooled catalytic reactor
A computational transport model is proposed for simulating the concentration, temperature, and velocity distributions in a wall-cooled fixed-bed catalytic reactor producing vinyl acetate from acetic acid and acetylene without assuming empirical Sc-t and Pr-t numbers or using the experimental coefficient of dispersion. The model consists of the basic differential equation of mass transfer with the recently developed (c(2)$) over bar - is an element of(c) model for its closure and the accompanied computational fluid dynamics and heat transfer models. With the present model, the radial and axial profiles of turbulent mass-transfer diffusivity D,, turbulent thermal diffusivity at, and turbulent kinematic viscosity nu(t), as well as their distributions in the reactor are obtained. It is found that the local ratios of nu(t)/D-t and nu t/alpha(t), or the local Prandtl (Pr-t) and Schmidt (Sc-t) numbers, are varying in the reactor, although the shapes of the nu(t), alpha(t), and D-t profiles show somewhat similarity. The simulated results are found to be in agreement with the experimental measurements reported by Valstar et al.(33).