Theoretical Investigation of the Compression Augmentation Effects of Variable Area Ejectors
Bibliographic record
Abstract
A theoretical analysis of a variable area ejector is presented. The flowfield is solved using a steady quasi-one-dimensional, inviscid control volume formulation assuming a fully mixed exit flow. A three parameter analytical wall pressure distribution is chosen to best match numerical results for ejector compression. While two of the parameters are pressure boundary conditions, the third is the minimum rocket stream pressure, and is found by using either a control volume or Riemann based approach. Both methods give very similar results for the minimum rocket pressure and nearly identical trends for its variation with total air pressure. The complete analysis procedure is used to study the performance of the constricted ejector at various operating conditions. Exit area constriction is found to have an overall beneficial effect on ejector compression. Although the theoretically predicted compression factors are about 30-40% higher than similar computational values, the exponential increase in compression with increasing constriction is well captured. Decreasing the exit area tended to increase thrust augmentation, with performance gains as high as 9% for the case with the highest area constriction.
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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 | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 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".