DESIGN OF A SERIES OF AIRFOILS FOR THE PSU ZEPHYRUS HUMAN-POWERED AIRCRAFT
Open Access
- Author:
- Tao, Tony S.
- Area of Honors:
- Aerospace Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Mark David Maughmer, Thesis Supervisor
Dr. Mark David Maughmer, Thesis Supervisor
Robert Graham Melton, Thesis Honors Advisor
Barnes Warnock Mccormick Jr., Faculty Reader
Dr. George A Lesieutre, Faculty Reader - Keywords:
- airfoil design
airfoil
aerodynamics
profil
xfoil
drela
eppler
maughmer
human
powered
aircraft
airplane
sailplane - Abstract:
- The Flight Vehicle Design and Fabrication class at The Pennsylvania State University (AERSP 204H/404H) is working on the design and construction of a human-powered aircraft (HPA) which will compete for The Kremer International Sporting Aircraft Competition hosted by the Royal Aeronautical Society. The aircraft design has matured over the last three years and the prototype design is being finalized. In an attempt to improve the performance of the aircraft, a series of airfoils for the major aerodynamic surfaces (wing, horizontal tail, and vertical tail) were designed specifically-tailored to the aircraft’s operational envelope, structural requirements, and desired handling qualities. The baseline planforms and structures of the aerodynamic surfaces are not altered in the design process. To design the airfoils, the surfaces were first analyzed with a 3-D lifting-panel method to determine the local lift coefficients corresponding to the HPA’s desired cruise range. Airfoil minimum thickness requirements are derived from minimum construction sizes for pre-preg carbon fiber and balsa wood. The handling characteristics were qualitatively considered into the airfoil design. The analysis showed that the wing airfoil should operate with a clmax of 1.6 at Reynolds number (Re) of 511000, a laminar drag bucket from cl=1.0 to cl=0.6 (within the range of Re=352000 to 716000) with a gentle exit at the higher corner of the bucket in all conditions, and a t/cmin of 12.3%. For the purpose of not introducing a higher load on the tail than previously designed, the pitching moment, cmac, of the wing airfoil should be no higher in magnitude than the baseline airfoil, the E395. The horizontal tail airfoil should have a drag bucket of cl=±0.3 in the Re range of 214000 to 385000 with a gentle exit on both sides, a clmax of 1.0 in the same Re range to give good tail authority, and a t/cmin of 10.6% to allow for structure. The vertical tail airfoil should be symmetrical and have low drag in at cl=0 while sloping off gently to a clmax of no less than 1.0 at a Re of 443000 to match the stability and control sizing used for the aircraft. Using these desired characteristics, pressure distributions are designed and, using the PROFIL program created by Dr. Richard Eppler, a series of airfoils were iterated upon until these requirements were met. The airfoils are analyzed in both PROFIL and XFOIL showing good agreement and generally successful satisfaction of design requirements. Further 2-D and 3-D analysis predict that these airfoils improve the performance of the aircraft at flight speeds from 10 m/s to 16 m/s while decreasing performance slightly at flight speeds below 10 m/s. Suggestions are made for future work that should yield improvements in airfoil and aircraft performance.