Klünker, AnnaAnnaKlünkerThai, Thanh TungThanh TungThaiSteuwe, EikeEikeSteuweWeiland, ChristianChristianWeilandSchade, YvonneYvonneSchadeKameke, Alexandra vonAlexandra vonKamekePadberg-Gehle, KathrinKathrinPadberg-Gehle2026-09-252026-09-252026-08-31Industrial & Engineering Chemistry research 65 (36): 19301–19315 (2026)https://hdl.handle.net/11420/65053Identifying coherent flow structures in chemical reactors is crucial for understanding the mixing dynamics, which is essential for optimizing reactor performance. We demonstrate the use of a transfer operator method to find coherent flow structures such as almost-invariant sets and coherent sets, which are characterized by minimal mixing with the surrounding fluid, in a lab-scaled stirred tank reactor using both simulated and experimental Lagrangian trajectory data. The proposed method further enables a detailed analysis of the mixing behavior by computing expected residence times and mixing times. Additionally, a Markov state model describes the macroscopic transport dynamics between compartments in the reactor.en1520-5045Industrial & engineering chemistry research2026361930119315.American Chemical Society (ACS)https://creativecommons.org/licenses/by/4.0/Technology::660: Chemistry; Chemical Engineering::660.2: Chemical Engineering::660.28: Types and Activities in Chemical PlantsDynamical compartments in stirred tank reactors and Markov state modeling for mixing quantification: A transfer operator approachJournal Article10.1021/acs.iecr.6c0117010.15480/882.1862011420/6332510.15480/882.1684410.15480/882.1746910.5281/zenodo.21874119