Multi-Objective Optimization of a Variable-Pitch Axial Flow Fan Design

This study performs a multi-objective optimization of a variable pitch fan. The design variables for the optimization considers the camber angle and setting angle of the fan blades, and to calculate the fan's performance and efficiency according to changes in these design variables, a meta model based on CFD modeling is constructed. The design objective functions for the variable pitch fan includes the design point efficiency and the standard deviation between the maximum efficiencies under variable pitch conditions. The optimal design point satisfying the two objective functions is derived from the Pareto front. This optimal design shows an improvement of 3.7 percentage points in design point efficiency compared to the initial design and demonstrated excellent characteristics of maintaining high efficiency over a wide flow rate range, with a standard deviation of 0.76% between the maximum efficiencies under different variable pitch conditions.