Strouhal Frequency Influence on the Vibration Specification for a Flat Blade Antenna Subject to Upstream Proturbances
Bibliographic record
Abstract
In order to enhance the usefulness and service life of today’s electronic warfare and surveillance aircraft, modernization programs often employ sophisticated upgrades to avionics requiring addition of antennae and/or radome type structures to the aircraft outer mold line. Often such additions may not be flush mounted and can be subject to the downstream flow region behind a proturbance. This region is typically characterized by a separated and turbulent flow which can significantly reduce the service life of impacted structure and/or protrusions such as an antenna. This paper presents a methodology for deriving a vibration design specification for a flat plate antenna subject to turbulent flow associated with an upstream proturbance such as a radome or bump. This approach was developed in support of a field failure investigation of a new antenna installed in the wake region of a radome on the P3 Orion aircraft. Specifically this paper addresses the derivation of a design usage definition for the antenna. The significance of Strouhal effects on structural response, and how to account for the Strouhal influence on frequency throughout the design envelope is thoroughly discussed. Additionally correlation between flight test data and an analysis model developed using the finite element method and a CFD/doublet lattice approach to define aerodynamic inputs is presented. Lastly the methodology for generating a single vibration design spectra for certification and qualification is detailed.
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 | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 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".