Characterization of single-phase flow hydrodynamics in a Berty reactor using computational fluid dynamics (CFD)

Abstract

This work studies the flow characteristics in a Berty reactor, a gradientless reactor for kinetic studies, using three-dimensional (3D) computational fluid dynamics (CFD), and a non-ideal continuous stirred tank reactor (CSTR) model. The state-of-the-art method could describe the flow characteristics including the dead volume, bypassing, and back-mixing inside the Berty reactor to effectively determine the suitable operating conditions with perfect mixing. The limitations of such behaviors are usually observed in most reactors and possibly in the Berty reactor. According to the CFD results, the dead volume could contribute up to 7.42% at atmospheric pressure, while it was observed to be slightly below 1% at a pressure above 6 atm due to improved recirculation inside the Berty reactor. The increment of pressure and impeller speed potentially improves the mixing characteristics of the Berty reactor with an abatement of dead volume. In contrast, the reduction of flow rate significantly leads to limited back-mixing. Bypassing in the Berty reactor could be observed especially in the temperature range of 350–450 °C due to excessively high velocity. This method can be used as a tool for characterizing non-ideal flows and enables researchers to reliably determine the suitable operating windows of perfect mixing for designing intrinsic kinetic experiments in the Berty reactor.