Flow Excited Resonance of a Confined Shallow Cavity in Low Mach Number Flow and Its Control
Bibliographic record
Abstract
Shallow cavities exposed to unbounded, low Mach number flow are generally weak aeroacoustic sources because their acoustic modes are heavily damped. This paper focuses on a cavity mounted on the wall of a duct to investigate the effect of “confinement”, i.e. solid boundaries close to the cavity, on the aeroacoustic response of shallow cavities in low Mach number flow (M < 0.3). It is found that the transverse acoustic modes of the duct-cavity combination are excited by the higher order modes of the cavity shear layer oscillations. The nature of the excitation mechanism as well as the effects of the cavity and duct dimensions are investigated by means of measurements of the amplitude and phase distributions of the acoustic pressure, complemented with flow visualization of the cavity shear layer oscillation. A method to predict the onset of resonance is also suggested. It is also shown that the acoustic resonance is effectively suppressed by a feedback control method, which generates a synthetic jet acting at the cavity upstream corner. The effect of the phase and gain of the controller transfer function is studied in some detail.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".