Influence of the Rotor Blade Pitch Angle on the Far-Field Noise Emissions of a Ducted Tail Rotor
Bibliographic record
Abstract
The present study focuses on the aeroacoustic aspects of ducted rotors that could be possibly used in future helicopter electrically driven tail rotor systems. Directivity measurements of the far-field acoustic pressure in the anechoic wind tunnel at Université de Sherbrooke have been performed varying the pitch angle of the rotor blades while maintaining the same rotational speed. The far-field noise shows a dominant tonal contribution over the whole audible frequency range. A level increase is seen when using the Pk109 configurations as well as the appearance of sub-harmonic humps. Also a broadening of the wake produced by the system is seen from the directivity plots. Preliminary results for the experimental campaign are achieved while the numerical simulations are achieved for one pitch angle and currently running for the other.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".