Two-Phase Flow Pressure Drop Hysteresis under Typical Operating Conditions for a Proton Exchange Membrane Fuel Cell
Bibliographic record
Abstract
Two-phase flow pressure drop hysteresis was studied under conditions typical of an operating PEM fuel cell. Two-phase flow hysteresis occurs when the gas and liquid flow rates are increased and decreased along the same path but exhibit different pressure drops. Variables studied include temperature (30-90oC), air stoichiometry (1-4), and gas diffusion layer. The results were analyzed relative to a baseline of fully humidified air at 75oC and a stoichiometry of 2 with a SGL Carbon 25 BC GDL. The percentage change between ascending and descending pressure drop is used to quantify the relative magnitude of the hysteresis. It was found that a sufficient air stoichiometry ({greater than or equal to}4) can reduce the hysteresis, the GDL properties affect the water breakthrough mechanism and shift the onset of the hysteresis zone, and higher temperatures reduce the relative magnitude of the hysteresis effect. These results correlate well with photographs of the cathode channel two-phase flow.
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) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".