Helicopter Rotor Blade Multiple-Section Optimization with Performance Considerations
Abstract
This paper presents advancements in a surrogate-based, rotor blade design optimization framework for improved helicopter performance. The framework builds on previous successes by allowing multiple airfoil sections to designed simultaneously to minimize required rotor power in multiple flight conditions. Rotor power in hover and forward flight, at advance ratio micro = 0.3, are used as objective functions in a multi-objective genetic algorithm. The framework is constructed using Galaxy Simulation Builder with optimization provided through integration with Dakota. Three independent airfoil sections are morphed using ParFoil and aerodynamic coefficients for the updated airfoil shapes (i.e., lift, drag, moment) are calculated using linear interpolation from a database generated using C81Gen/ARC2D. Final rotor performance is then calculated using RCAS. Several demonstrative optimization case studies were conducted using the UH-60A main rotor. The degrees of freedom for this case are limited to the airfoil camber, camber crest position, thickness, and thickness crest position for each of the sections. The results of the three-segment case study show improvements in rotor power of 4.3% and 0.8% in forward flight and hover, respectively. This configuration also yields greater reductions in rotor power for high advance ratios, e.g., 6.0% reduction at micro = 0.35, and 8.8% reduction at micro = 0.4.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 10, 2021
- Accession Number
- AD1137635
Entities
People
- Ian D. Dettwiller
- Joon W. Lim
- Luke D. Allen
- Robert B. Haehnel
Organizations
- Engineer Research and Development Center
- United States Army Aviation Branch