Hydrodynamic Optimization and Bioelectrochemical Performance of a Dual‐Chamber Microbial Fuel Cell: A CFD‐Assisted Evaluation of Stirring Effects for Textile Wastewater Treatment

The optimization of hydrodynamic conditions in microbial fuel cells (MFCs) is critical to enhancing both pollutant removal and electricity generation. This study evaluates the impact of impeller‐driven mixing applied to anaerobic MFCs on biomass suspension, dye degradation, and power output. Activated sludge (100–300 g/L, equivalent to 2.0–6.0 g/L TS) was combined with a synthetic dye solution and operated under stirring speeds of 25, 75, and 125 rpm. A CFD framework based on the Eulerian multiphase approach and the RNG k – ε turbulence model was implemented in ANSYS Fluent to simulate liquid–solid interactions, predict biomass distribution, and compare the results with experimental measurements. CFD predictions aligned closely with measurements (error < 3%). At 125 rpm, a homogeneous sludge suspension was achieved, preventing sedimentation and promoting optimal substrate‐biofilm contact. Under these conditions, dye removal reached 78% and power density increased to 0.951 W/m 2 . Reduced stirring (25 rpm) caused biomass accumulation at the bottom, lowering color removal to 35% and power density to 0.231 W/m 2 .