Effects of surface wettability on the aerodynamics of wind-driven droplets at the verge of shedding
Bibliographic record
Abstract
An experimental study was conducted to investigate the time-averaged aerodynamics of sessile droplets at the verge of shedding on hydrophilic and hydrophobic surfaces. A high-resolution particle image velocimetry system was used to measure/reconstruct the velocity and pressure fields in the droplet symmetry plane and obtain the time-averaged aerodynamic loading. It was found that the stagnation angle (the angle bounded by the substrate and the ray emanating from the droplet center connecting to the stagnation point) decreases with decreasing contact angle due to the shrinking size of the horseshoe vortex. The air pressure reaches the maximum near the stagnation point and its minimum near the droplet apex where flow separation occurs. In the near wake of droplets, a recirculation region, where the velocity reduces to nearly zero and the pressure is low, is generated due to the flow separation. The normalized length of the recirculation region decreases with increasing contact angle since droplets with higher contact angles need flows with lower Reynolds number to reach the point of shedding. In addition, the aerodynamic drag over droplets was evaluated by the wake integral method, analyzing the contribution of momentum deficit, Reynolds stress, and pressure deficit. The drag coefficient of the droplets, at the verge of shedding, was independent of the contact angle. This work shows that the drag coefficient of droplets with different contact angles at the verge of shedding can be similar even though the droplet shape, Reynolds number, and flow structures are different.
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 | 0.000 |
| 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 | 0.000 |
| Scholarly communication | 0.000 | 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".