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arXiv · 2603.13996

Dynamical compartments in stirred tank reactors and Markov state modeling for mixing quantification: a transfer operator approach

Anna Klünker·Thanh Tung Thai·Eike Steuwe·Christian Weiland·Yvonne Schade·Alexandra von Kameke·Kathrin Padberg-Gehle
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Abstract

Identifying 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.

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Anna Klünker, Thanh Tung Thai, Eike Steuwe, Christian Weiland, Yvonne Schade, Alexandra von Kameke, Kathrin Padberg-Gehle. 2026-03-14. Dynamical compartments in stirred tank reactors and Markov state modeling for mixing quantification: a transfer operator approach. https://arxiv.org/abs/2603.13996

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