Applicability of flow-rate-independent discharge coefficients in purpose-provided, interior natural-ventilation openings
Bibliographic record
Abstract
Natural ventilation involves low pressures, necessitating large interior ventilation openings (ventilators) with low airflow resistance in interior partitions, allowing required ventilation airflow. These ventilators are detrimental to the noise isolation between spaces. Design methods often use flow-rate-independent discharge coefficients, which rely on a high-Reynolds-number (Re) assumption. This paper evaluates this assumption for purpose-provided ventilators, based on theory, field measurement data and prediction. If a high-Re discharge coefficient is used to predict airflow at low Re, the flow rate will be over-predicted and the system under-designed. Reynolds numbers in some existing interior ventilators are low enough that flow rates are inaccurately described by a high-Re discharge coefficient. If the ventilator is highly restrictive to flow or if the hydraulic diameter of the flow path is very small, low-Re behaviour may be critical to system design.
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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 | 0.002 | 0.009 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| 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 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".