Aeroacoustic Source Distribution Around Four Cylinders Orientated in a Square
Bibliographic record
Abstract
An experimental investigation of the flow-acoustic coupling of four cylinders arranged in a square configuration with a spacing ratio in the proximity interference range subject to forced acoustic resonance is presented. The aeroacoustic characteristics and the flow field structures are investigated at various sound pressure levels to study its influence on the “lock-in” behaviour of the separated flow and the corresponding distribution of the resonant acoustic sources. Two mainstream flow velocities were selected for testing that corresponded to flow field conditions before acoustic-Strouhal coincidence of the vortex shedding frequency with the natural acoustic frequency of the duct and to flow field conditions after acoustic-Strouhal coincidence. Increasing the sound pressure level was found to slightly increase the range of flow velocities with which the acoustics could entrain the vortex shedding regime. Increasing the sound pressure level was also found to shorten the length of the most intense vortical structures in the shear layers emanating from the upstream cylinders and hence also shifted the dominant acoustic sources upstream. Spatial distributions of the net acoustic energy suggests that the mechanism triggering acoustic resonance of the four cylinders is shear layer instability, which is similar to that observed for two tandem cylinders.
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 | 0.001 |
| 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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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".