Heat exchanger/reactors (HEX reactors): Concepts, technologies: State-of-the-art

Process intensification is a chemical engineering field which has truly emerged in the past few years and is currently rapidly growing. It consists in looking for safer operating conditions, lower waste in terms of costs and energy and higher productivity; and away to reach such objectives is to develop multifunctional devices such as heat exchanger/reactors for instance. This review is focused on the latter and makes a point on heat exchanger/reactors. After a brief presentation of requirements due to transposition from batch to continuous apparatuses, heat exchangers/reactors at industrial or pilot scales and their applications are described

Flow structures and heat transfer characteristics in fan flows with and without delta-wing vortex generators

[[abstract]]Effects of an external delta-wing vortex generator on the flow and heat transfer characteristics in fan flows and uniform flows were experimentally investigated and compared. A heated plate, installed on the bottom wall of a duct, was used as the heat transfer surface. Three-component mean and fluctuating velocity measurements were conducted using a laser Doppler velocimetry to characterize the flow structures and to obtain the near-wall flow parameters, including the axial mean velocity, axial vorticity and turbulent kinetic energy. Temperatures on the heat transfer surface were measured using thermocouples to obtain the Nusselt numbers. Results show that the external delta-wing vortex generator in fan flows has little overall effect on the near-wall averaged axial mean velocity and axial vorticity, but increases the turbulent kinetic energy, in the investigated X/D ranges. The increase in the turbulent kinetic energy by the delta-wing has little effect on heat transfer in the inherently vortical fan flows. Consequently, the delta-wing vortex generator in fan flows has little effect on the heat transfer augmentation.[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙