In this work, we present the dynamic mode decomposition of natural convection in a non-Newtonian fluid within a closed cavity. The physical model considers mass and momentum transport, Ostwald-de Waele power-law for a description of non-Newtonian viscosity, and Boussinesq approximation for description of density-temperature dependency. The model is numerically solved with generalised finite differences, explicit Euler stepping and Chorin's projection method. The implemented solution procedure is tested by comparison of computed results with published data with good agreement achieved. We introduce dynamic mode decomposition and demonstrate its performance on a synthetic case. The main part of this work is focused on a mode analysis of natural convection of non-Newtonian fluid in a closed cavity. We analyse different non-Newtonian fluids in two different geometries where we are in particular interested in the transition from stationary to oscillatory solutions. In addition, we identify elements of dynamics that are not present in Newtonian fluids and show that the pseudoplastic non-Newtonian fluids exhibit richer dynamics in comparison
with Newtonian fluids.
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