Fan Exit Research Articles

Composite fan exit guide vanes for high bypass ratio gas turbine engines

Various composite materials were identified for reduced weight applications as fan exit guide vanes in high bypass ratio gas turbine engines. Candidate materials, airfoil geometry and ply orientation were evaluated using NASTRAN finite element analysis. A vane core and shell design approach utilizing several different fiber orientation concepts was selected and variations in bending and torsional stiffness were documented. Material suppliers and airfoil fabricators were selected to provide panels and airfoils which were inspected, environmentally conditioned and tested. Static and dynamic airfoil tests established durability characteristics for a range of composite material/design approaches.

Engine Environmental Effects on Composite Behavior

The NASA Lewis Research Center has conducted a series of programs intended to investigate and develop the application of composite materials to turbojet engines. A significant part of that effort was directed to establishing the impact resistance and defect growth characteristics of composite materials over the wide range of environmental conditions found in commercial turbojet engine operations. Both analytical and empirical efforts are involved. This paper summarizes the experimental programs and the analytical methodology development as well as an evaluation program for the use of composite materials as fan exit guide vanes.