Net flow characteristics inside an oscillatory reactor equipped with 3 orifice baffles

Abstract

Oscillatory Baffle Reactors (OBR) are often found in industrial processes. This type of device is specially intended for chemical reactions with high residence time and moderate or high mixing requirements (usually achieved by increasing the Reynolds number). In order to meet both objectives, a standard pipe heat exchanger would be too big. Therefore, OBRs are designed to produce, on the one hand, a low Reynolds number net flow, which results in a high residence time, and, on the other hand, an oscillatory flow is superimposed to increase mixing. This last effect is enhanced by inserting baffles into the pipe, so that their presence, together with the oscillatory flow, produce high pulsating radial velocities to optimize mixing. Besides, as an additional benefit, heat transfer enhancement due to the enhanced convection is also expected. Prior studies have proved OBRs to be very effective for the mentioned objectives, and annular baffle designs have been studied in depth. However, to date, there are only preliminary studies regarding other baffle geometries. The present work presents a complete study of an oscillatory reactor which uses three orifice baffles. The study combines different experimental techniques which provide a full overview of the flow field and its characteristics.