3D Analysis of Heat Transfer Intensification by Re‐Entrance Flow Pin‐Fins Microstructures with a Highly Thermal‐Conductive Plate

Abstract

Joule heat-induced hot-spot formation sets severe limits in the operation of continuous annular electrochromatography (CAEC), a new concept for preparative separation as an analog to analytical capillary electrochromatography (CEC). This may lead to eluent flow perturbance, even to boiling, which would massively weaken separation efficiency and may even hamper the stationary phase used for separation. For reasons of system integration and high-efficiency heat transfer, micro flow heat exchangers are considered with a separate coolant flow. A 3D numerical analysis of the heat transfer of water single-phase laminar flow in a square microchannel and different arrays of micro pin-fins was carried out using COMSOL Multiphysics. Several advanced materials with low electric conductivity and at the same time with high heat conductivity were put forward to be used in the CAEC system. As essential design point, it is proposed to constitute the micro heat exchanger from two different parts of the CAEC system, namely a microstructured pin-fins plate and a so-called conductive plate.

Separation, Hydrodynamics, and Joule Heating Effects in Continuous Annular Electrochromatography

“…In order to remove the generated Joule heating during the experiments, the integration of a heat exchanger (HX) in both applications was necessary. Heat exchange in the annular system was achieved using the complete inner cylinder in contact with the cooling media [30].…”

CO2 splitting in a micro DBD reactor with an electrode containing charge injector parts

“…In the at electrode reactor, the temperature difference between the gas temperature and the electrode temperature was about 90 K. However, this difference in the pyramid micro DBD reactor seems to be much smaller. The pyramids create natural obstacles to the gas ow and introduce a split-and-recombine ow pattern which enhances heat transfer as compared to laminar ow between the two at electrodes [49]. In addition, the gap size was reduced in the pyramid reactor by a factor of 2 resulting in a higher super cial CO 2 ow rate, which further increased heat transfer between the plasma and the cold electrode surface.…”

A View Through Novel Process Windows

“…In contrast, Novel Process Windows aim to boost chemical production through unconventional chemistry, utilizing harsh reaction conditions. [3][4][5][6][7] At the core of this approach is the notion that the intrinsic kinetics behind many chemical processes can be very fast, if the right conditions are applied. Since such conditions are not commonly found in today's laboratories, intrinsic kinetics are typically much lower however.…”