A perspective on the past, the present, and the future of computational fluid dynamics (CFD) in flow chemistry

Flow chemistry is the future of chemical processing. It represents a significant advance in energy consumption and waste generation regarding operations in batch and continuous flow macroscopic equipment since the transport rate (of mass, heat, photons, electrons, etc.) is tremendously intensified. In parallel, computational fluid dynamics (CFD) is part of engineering’s future. Digitalization of transport processes (involving fluid flow and scalar transport, e.g., species, energy, etc.) is the state-of-the-art for designing, optimizing, and scaling chemical reactors, separation and purification units, heat exchangers, etc. This perspective initially presents relevant fundamental CFD concepts applicable to any field. In the sequence, an overview of applications of CFD in flow chemistry reported in the literature over the last two decades is presented, highlighting the evolution of complexity and variety of topics investigated (ranging from single-phase flow optimization to multiphysics cases involving coupling of multiphase flow and external forces—e.g., ultrasound and electric field). Next, the contributions of our research group in CFD in flow chemistry are presented—with a focus on photocatalytic and electrocatalytic systems—and accompanied by highlights about our personal experience. Further discussion about strengths, limitations, and opportunities for CFD in flow chemistry is presented, highlighting to the reader the gaps that should be in the spotlight over the next few years, followed by our final remarks. After reading this perspective, the reader (either a starter in this field or an expert) will be able to identify how CFD has evolved in flow chemistry over the years and what are the next directions from the authors’ point of view.