Performance comparison of a structured bed reactor with and without a chimney tray on the gas-flow maldistribution: A computational fluid dynamics study

Abstract

In the present paper, two configurations of structured reactors (with and without) chimney tray placed below the packed bed have been investigated to study their effect on maldistribution factor and pressure drop characteristics. A simulation result based on a three-dimensional computational fluid dynamics was involved using ANSYS Fluent. First, maldistribution factors without chimney tray were calculated and compared to the results taken from the literature. The results were found to be in good agreement with the experimental data of Yuan et al. Second, the reactor with a chimney tray was modeled in Fluent, and steady-state simulations were performed. The uniformity due to the turbulence of the fluid was carried out using different turbulence models, and the velocity profiles along the axial direction inside the reactor were obtained. As a result, the comparison shows that the presence of a chimney tray yields lower maldistribution factor enhancement by 23% compared to the conventional structured reactor under the same operating condition. The effect of the plate orientation is also determined, and it is found that the maximum pressure drop is achieved through the rows with an orientation angle of α = 45° up to 2.3% higher than of α = 0° and α = 90°.