Investigation of Flow and Heat Transfer Characteristics in Microchannels with Fins

Abstract

A highly efficient thermal management is imperative to overcome the main challenges associated with heat extraction requirements in electronics. In this study, the flow and heat transfer characteristics of microchannels with various types of fins were numerically analyzed for Re = 0–500 (Re: Reynolds number). Investigation of the aspect ratio, incident angle, and smoothness as well as the flow and heat transfer behaviors revealed the exceptional performance of the optimized fin structure, up to a performance evaluation criterion of 1.53. At large Re values, the fin with a high aspect ratio, small incidence angle, and high smoothness showed the best performance, as it avoids stagnation zones because of flares and sharp corners and simultaneously leads to boundary layer destruction and redevelopment. Interestingly, the microchannel without internal microstructures performed well at small Re values. Among all the designed variables, the influence of the incident angle was superior owing to its ability to generate significant vortices by periodically changing the channel cross-sectional area and flow direction. The conclusions can be innovatively generalized to other microchannels with fins.