Development and Testing of a Passive Variable-Pitch Propeller
| Autor: | Ashok Gopalarathnam, Charles E. Hall, Stearns B. Heinzen |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Engineering
animal structures business.industry Blade pitch Acoustics Propeller Aerospace Engineering macromolecular substances Aerodynamics P-factor humanities Constant speed propeller Variable pitch propeller otorhinolaryngologic diseases Advance ratio business psychological phenomena and processes Marine engineering Envelope (motion) |
| Zdroj: | Journal of Aircraft. 52:748-763 |
| ISSN: | 1533-3868 0021-8669 |
| DOI: | 10.2514/1.c032595 |
| Popis: | A novel approach to passive propeller blade pitch variation is investigated. To effect passive pitch changes, the propeller blades are allowed to pivot freely about a radial axis, and aerodynamic pitching moments are tailored to give favorable blade pitch angles over a wide range of advance ratios. Computational modeling of the system indicated that a large expansion of the efficient operating envelope is possible, compared to a fixed-pitch propeller. Wind-tunnel experiments corroborated the computational results and demonstrated that the propeller maintained near-peak efficiency by passively adjusting blade pitch angles by over 15 deg to the match changing advance ratio. The passive variable-pitch propeller was then successfully demonstrated in flight on an unmanned aerial vehicle. Using tailored aerodynamics in place of active control allows this performance improvement to be realized at a fraction of the weight and complexity of a traditionally actuated variable-pitch propeller. The concept enables the... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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