Modelling Local Dynamic Pressure Within Inflatable Sports Balls
Bibliographic record
Abstract
This study used a coupled Eulerian Lagrangian (CEL) approach to model the air within a football (soccer ball) during two types of impacts. Conventional modelling techniques (and those used in all previous football finite element models known by the author) utilize a uniform pressure method incapable of accounting for spatial pressure variation. Internal pressures and deformations for the CEL and uniform pressure models were within a few percent of each other, indicating good agreement between pressurization techniques. By necessity, the air was defined with different methods in each model and this may have contributed to a discrepancy in maximum internal pressure. Using the CEL model, the pressure wave generated at impact was observed to travel from one side of the ball to the other at the speed of sound. Though the CEL model helped illustrate the impact scenario, there were no clear distinctions that gave it an advantage over the uniform pressure method for simple impact analysis.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| 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".