Numerical Evaluation of Transport Phenomena in a T-junction Microreactor with Coils of Different Configurations

Microchannel T-junction configuration is used in chemical processing for passive mixing and reactions, because of its relatively easy control of the reaction environment. However, poor mixing and low reaction rate are some of the main drawbacks of this design. This study proposes mass-transport enhancement in a microchannel T-junction by utilizing various configurations of coiled base channel design (e.g., conical spiral, in-plane (flat) spiral, and helical spiral coils). Their mass-transport performance is investigated numerically and compared with that of the conventional straight microchannel T-junction. Laminar flow of gas flow with reactions is investigated using a three-dimensional computational fluid dynamics (CFD) model. Four different microchannel designs, three different channel Reynolds numbers, and three different helical coil diameters are investigated. The coils are made of a square cross-section tube. The results indicate that the coiled base channel displays improved mixing and conversion ...

[1]  T. Liou Flow visualization and LDV measurement of fully developed laminar flow in helically coiled tubes , 1992 .

[2]  Krishna D.P. Nigam,et al.  A Review on the Potential Applications of Curved Geometries in Process Industry , 2008 .

[3]  Krishna D.P. Nigam,et al.  Mixing in curved tubes , 2006 .

[4]  Arun S. Mujumdar,et al.  Numerical investigation of laminar heat transfer performance of various cooling channel designs , 2011 .

[5]  Yangcheng Lu,et al.  Intensification of Catalytic Oxidation with a T-junction Microchannel Reactor for Deep Desulfurization , 2008 .

[6]  Nam-Trung Nguyen,et al.  Micromixers?a review , 2005 .

[7]  Adeniyi Lawal,et al.  Numerical and experimental studies of mixing characteristics in a T-junction microchannel using residence-time distribution , 2009 .

[8]  A. Mujumdar,et al.  Numerical evaluation of laminar heat transfer enhancement in nanofluid flow in coiled square tubes , 2011, Nanoscale research letters.

[9]  Yannick Hoarau,et al.  Slug flow in curved microreactors: Hydrodynamic study , 2007 .

[10]  S. Pushpavanam,et al.  Experimental and Numerical Investigations of Two-Phase (Liquid−Liquid) Flow Behavior in Rectangular Microchannels , 2010 .

[11]  Paolo Canu,et al.  Simulation and interpretation of catalytic combustion experimental data , 2001 .

[12]  K. Nigam,et al.  Augmentation of heat transfer performance in coiled flow inverter vis-à-vis conventional heat exchanger , 2010 .

[13]  M. Paraschivoiu,et al.  Single-phase fluid flow and mixing in microchannels , 2011 .

[14]  Krishna D.P. Nigam,et al.  Coiled flow inverter as an inline mixer , 2008 .

[15]  Hassan Aref,et al.  Chaotic advection by laminar flow in a twisted pipe , 1989, Journal of Fluid Mechanics.

[16]  Robert W. Dibble,et al.  HYDROGEN ASSISTED CATALYTIC COMBUSTION OF METHANE ON PLATINUM , 2000 .

[17]  Krishna D.P. Nigam,et al.  Numerical studies of a tube-in-tube helically coiled heat exchanger , 2008 .

[18]  Adeniyi Lawal,et al.  Numerical study on gas and liquid slugs for Taylor flow in a T-junction microchannel , 2006 .

[19]  Somchai Wongwises,et al.  A review of flow and heat transfer characteristics in curved tubes , 2006 .

[20]  A. Mujumdar,et al.  Laminar convective heat transfer for in-plane spiral coils of noncircular cross sections ducts: A computational fluid dynamics study , 2012 .

[21]  Norbert Kockmann,et al.  Numerical and experimental investigations on liquid mixing in static micromixers , 2004 .

[22]  Ismail Teke,et al.  Turbulent forced convection in a helically coiled square duct with one uniform temperature and three adiabatic walls , 2005 .

[23]  K. Nigam,et al.  Fluid Flow and Heat Transfer in Curved Tubes with Temperature-Dependent Properties , 2007 .

[24]  D. J. Kraus,et al.  Integrated Microreactor System for Gas-Phase Catalytic Reactions. 1. Scale-up Microreactor Design and Fabrication , 2007 .

[25]  Arun S. Mujumdar,et al.  A numerical investigation of some approaches to improve mixing in laminar confined impinging streams , 2005 .

[26]  Paisarn Naphon,et al.  Thermal performance and pressure drop of the helical-coil heat exchangers with and without helically crimped fins , 2007 .

[27]  Krishna D.P. Nigam,et al.  Modelling of a coiled tubular chemical reactor , 2001 .

[28]  A. Mujumdar,et al.  Three-Dimensional Analysis of Flow and Mixing Characteristics of a Novel In-Line Opposing-Jet Mixer , 2007 .

[29]  Laxminarayan L. Raja,et al.  A critical evaluation of Navier–Stokes, boundary-layer, and plug-flow models of the flow and chemistry in a catalytic-combustion monolith , 2000 .

[30]  A. Mujumdar,et al.  Evaluation of the heat transfer performance of helical coils of non-circular tubes , 2011 .

[31]  Yannick Hoarau,et al.  Numerical modeling of polystyrene synthesis in coiled flow inverter , 2011 .