Optimization of the Mass Transfer of a Mixed Flow Impeller Using Response Surface Methodology

ABSTRACT This work presents the geometric optimization of an axial–radial impeller (ARI) hybrid to maximize gas–liquid mass transfer using response surface methodology. A Box–Behnken design was applied to evaluate the effects of blade number, inclination angle, and aspect ratio on the volumetric mass transfer coefficient ( K L a ). The optimized configuration was experimentally validated and compared with the original ARI and a Rushton turbine under fermentation‐relevant conditions. Results showed an 8% increase in K L a , and a 25% reduction in power consumption relative to the original design. The optimized ARI demonstrated superior performance at medium‐to‐high aeration and agitation, confirming the effectiveness of systematic geometric optimization.