CFD Models for Liquid-Phase Chemical Reactors: Validation of PDF and Large-Eddy Simulations Using Stereo PIV and Reactive PLIF Experiments

Iowa State University, Ames IA

Investigators

Abstract

Research: Macroscopic models based on computational fluid dynamics (CFD) have potential for improving reactor design in the chemical process industries. Better reactor design can also lead to reducing pollution by producing less toxic byproducts. Numerous chemical processes involve fast chemical reactions for which the product distribution is affected by turbulent transport. For these systems, using CFD effectively depends on the development and validation of micromixing models needed to describe the complex interactions between turbulent mixing and chemical reactions at the sub-grid scale. Commercial CFD codes have shortcomings related to model development and validation that must be overcome before CFD can reach its full potential for developing environmentally benign, commercially efficient chemical technologies. The PIs will focus on developing CFD models for turbulent liquid-phase chemical reactions. They plan to obtain experimental data for turbulent flow field and concentrations fields inside the liquid phase for two canonical reactor geometries under carefully controlled operating conditions using simultaneous stereo-particle-image velocimetry (SPIV) and reactive planar laser-induced fluorescence (RPLIF). On the modeling side they will develop CFD models for turbulent reacting flows based on large-eddy simulation (LES) of the flow and probability density functions (PDF) for the chemical species. These models contain well-defined unclosed terms that will be extracted from SPIV and RPLIF data for two canonical turbulent flows: a confined planar jet and a confined sudden-expansion planar jet. More generally, the knowledge gained in this project will enhance the state of the art in measurement techniques for simultaneous velocity and reacting scalar statistics using SPIV and RPLIF in liquid-phase turbulent flows. Broader Impacts: The PIs have a long history of recruiting students from underrepresented groups to become involved in their research. These outreach activities are facilitated by many institution-wide minority and women recruitment programs at Iowa State University. K-12 students will be invited to work in the PI's laboratory as summer research interns. The reduction of pollution and toxic byproducts caused by poor product selectivity is a critical step towards the development of environmentally benign, commercially efficient chemical technologies for the production of fuels, materials, chemicals and pharmaceuticals.