2024 AIChE Annual Meeting
(189a) Analysis of Turbulent Reacting Flows and Combustion Processes Using the Hierarchical Parcel Swapping Model
Turbulent combustion is noted for its complexity and computational expense for accurate solution due to the presence of a wide range of time and length scales. Several models have been used with varying degrees of success, but research to find a good model is still active. In this study, we present a novel model for simulating combustion called Hierarchical Parcel Swapping (HiPS). It operates based on a binary tree without the need to solve Navier-Stokes equations. The tree consists of different nodes and parcels at the bottom, which represent different length and time scales of the flow and eddy events are simulated by swapping the subtrees. In this model, mixing and reactions take place within the parcels, which occur when eddy events trigger parcel swapping. We investigate parallel/series reactions (A + B → R, R + B → S) with constant and varying rates, as well as detailed combustion mechanisms that allow for unique treatment of complex phenomena including flame extinction and soot formation. For the simple parallel reactions, we will investigate the effect of Damkohler number on selectivity. For combustion, we will present the sensitivity of results to initial conditions, differential diffusion, and mixing intensity. We show how this work deepens our understanding of chemical kinetics in turbulent flows and validates the efficacy of HiPS as an efficient computational tool for complex turbulent combustion processes, and turbulent reacting flows in general.