Design of jet engine component : fan blade

Abstract

Improved fuel efficiencies through fan blade mass reductions are possible, owing to advances in newer manufacturing processes such as 3D printing. Complex internal geometries within engine fan blades can be designed to allow for further mass reductions, while adhering to energy and strength requirements. This report focuses on the effect of various internal geometry designs on deformation behaviour and structural requirements of an engine fan blade. Comparison analysis was made between a base model featuring a thickened leading edge, and four design models featuring stiffeners of varying geometries along the leading edge. Results show that all four design models achieved average mass reductions of 29% relative to the base model. Furthermore, a shorter distance between leading edge stiffeners is observed to correlate with further mass reductions; a 50% decrease in stiffener gap, from 10mm to 5mm, corresponds to a further 2% leading edge mass reduction from 0.882kg to 0.864kg. Adopting thicker leading edge stiffeners tend to have a negligible effect on mass reductions, as the decrease in leading edge thickness and mass is offset by increases in stiffener mass. While leading edge thickness reductions can also be achieved by increasing the area of stiffened leading edge region, net mass reductions is negligible due to increases in stiffener areas and hence masses.