Three-dimensional simulation and analysis of the fluid flow in contraction–expansion array microchannels

Abstract

The primary objective of this work is to investigate the flow characteristics in contraction–expansion array microchannels with a rectangular cross-section. Flow in channels of this geometry is often found in heat exchangers, as a part of functional elements of microfluidic devices applied in medicine, chemical engineering, etc. To achieve such simulations in three-dimensional case a numerical approach based on the Boundary Element Method accelerated both via the Fast Multipole Method, and heterogeneous computing architecture (multicore CPUs and graphics processors) is utilized. We explore numerically the velocity fields formed in the regions of lateral caverns of rectangular shape. Obtained results have been analyzed in detail for different ratios of cavern length and width, as well as their relative location. In addition, a study of the features of secondary flow formation in the regions of microchannel expansion and their changes depending on the variation of the microchannel height has been carried out. The hydrodynamic resistance and flow regimes in microchannels with different hydraulic diameter of the main part and configuration of side caverns were investigated. The obtained results are expected to be significant for selecting and optimizing contraction–expansion microchannel configuration for a wide range of applications.