Transport phenomena

Studying the transport phenomena inside the microreactors can help us understand, optimize and determine the operative parameters of chemical and biochemical reactions. The convection and diffusion transport of species in micro dimensions may be precisely determined, since the flow regimes are well known and therefore there is no need for use of simplified models such as film theory, which is based on overall mass and heat transport coefficients.
The basis of the mathematical description of transport phenomena at laminar flow conditions is the Navier-Stokes conservation equation for momentum (Eq. 1), coupled with mass conservation equation (Eq. 2), which enable us to precisely determine the velocity and flow profile inside the microchannel.

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Obtaining the flow profile inside the microreactor is a necessity for prediction of species transport, because the convection component is a crucial component of the species conservation equation (Eq. 3).

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If we simultaneously solve equations 1-3 with the use of appropriate boundary conditions, initial condition and physical domain, we can obtain solutions to concentration distribution as well as chemical and biochemical reaction rates inside the microreactor, which help us design the microchannel geometry and obtain the optimal operating parameters, such as flow rate, temperature and pressure.