Heat-Transfer Analysis and Improved Mixing in Multifunctional Microreactor Using Sapphire Window and Infrared Thermography

摘要: This work is devoted to heat-transfer analysis and mixing intensification of reactants in a microchannel. We measure the two-dimensional heat flux generated by a HCL/NaOH chemical reaction with an infrared (IR) camera by performing simultaneous temperature measurements on both sides of a sapphire plate in contact with the fluid flow. The reaction takes place in a T-shaped rectangular microchannel (500 µm× 50 µm× 38 mm) made of PDMS and closed with a 1 mm thick sapphire plate coated with an opaque dielectric layer on the fluid side and a striped layer on the other. We show that using this heat-flux distribution measurement makes it possible to obtain the reaction enthalpy of a well known neutralization reaction. The second aim of this work is to intensify the mixing of chemical species without modifying the microreactor geometry. For this purpose, we investigate experimentally the effect of flow pulsation …