Abstract:
This project envisaged the material and structural assessment of lift beams of the aircraft, which are transverse structural members and are the support for stub wings. Three beams provide forward, mid and aft attachment points and were analyzed in the course of this research for intended design load assessment. Material characterization was performed through OES and EDS using SEM. Obtained values were verified with standard alloy composition of Aluminum Alloy confirming the alloy grade, while hardness measurements and metallography verified temper state and processing routes.
Physical measurements were made for the creation of geometry in CAD software Pro Engineer. Generated CAD models were imported through direct interface to ANSYS for structural analysis through FEM. Since no design data was available as to the loading conditions of the wing and its associated supports, CFD analysis was resorted to for the evaluation of flight loads. Wing models for CFD analysis was generated through Pro Engineer and same was imported to GAMBIT preprocessing environment of FUENT for mesh generation in the form of IGES format. Air flow was generated at a velocity of 190 knots and installed angle of attack of 190 with the centre line of the aircraft. CFD analyses provided lift and drag coefficients thus enabling calculation of lift and drag forces for the wing geometry.
Stress and strain plots were obtained from FEM analysis, verifying the structural integrity of the structure under review, maximum Von-Mises stress being lower than the yield strength of the material. From the obtained stresses and strain values, fatigue life was estimated for the beams using Morrow’s equation to cater for mean stress effects using strain life approach.
