Optimization of Centrifugal Fan Efficiency Based on Volute Meridional Inlet Width and Stepanoff Number Using CFD and Kriging-Based Response Surface Method

Abstract

The present work optimizes the efficiency of a centrifugal fan by applying Computational Fluid Dynamics and a Kriging-based response surface methodology. The aim is to improve fan efficiency in the low to medium pressure values while maintaining the existing broad pressure range performance. Volute meridional inlet width and Stepanoff number were chosen as variables. Their effects on total efficiency and volume flow rate were evaluated by applying incompressible steady state Ansys CFX simulations after mesh independence confirmation. A Design of Experiments framework at nine design points was generated by using Latin Hypercube Sampling method. A kriging metamodel was then generated and validated at 7 points with a relative average absolute error lower than 3%. The optimum design was found at a volute meridional inlet width of about 0.27 m and a Stepanoff number of 0.3. The optimized geometry results in an average relative efficiency improvement of approximately 6.79% in the 0–900 Pa range.