Turbulence in a microscale planar confined impinging-jets reactor.

Confined impinging-jets reactors (CIJR) offer many advantages for rapid chemical processing at the microscale in applications such as precipitation and the production of organic nanoparticles. It has been demonstrated that computational fluid dynamics (CFD) is a promising tool for "experiment-free" design and scale-up of such reactors. However, validation of the CFD model used for the microscale turbulence applications requires detailed experimental data on the unsteady flow, the availability of which has until now been very limited. In this work, microscopic particle-image velocimetry (microPIV) techniques were employed to measure the instantaneous velocity field for various Reynolds numbers in a planar CIJR. In order to illustrate the validation procedure, the performance of a particular CFD model, the two-layer k-epsilon model, was evaluated by comparing the predicted flow field with the experimental data. To our knowledge, this study represents the first attempt to directly measure and quantify velocity and turbulence in a microreactor and to use the results to validate a CFD model for microscale turbulent flows.