Propeller Fan Wing Serration Design to Reduce Eddy Interference

The patent applies parameter changes by modifying the geometry of the protrusion's rear edges through serration shapes. The outer circumferential rear edge is given a first serration shape and the inner circumferential rear edge is given a second serration shape, with specific length ratio constraints between the serrations. This geometric parameter modification controls eddy generation while preserving the airflow control benefits of the protrusion, thereby resolving the contradiction between improving fan efficiency and reducing harmful eddies.

The patent resolves this contradiction by applying parameter changes through carefully constrained serration geometry. The first and second serration shapes are designed with specific length ratio relationships, and the serrations are formed as continuous undulating patterns along the rear edges. This approach reduces eddy interference through geometric optimization while maintaining manufacturing feasibility and avoiding excessive structural complexity.

The patent resolves this contradiction by applying parameter changes to the protrusion geometry. The serration shapes on the outer and inner circumferential rear edges, with their specific length ratios, control the flow separation and eddy formation characteristics. This allows the protrusion to be optimized for airflow management while the serrations simultaneously control eddy size, preventing the trade-off between performance enhancement and eddy generation.