An Experimental Investigation of Turbulent Flow in Concentric Annulus Using Particle Image Velocimetry Technique
Bibliographic record
Abstract
Fully developed turbulent flow in a concentric annulus is encountered in many engineering problems including food, chemical as well as oil industry applications. Because of nonlinear radial variation of total shear stress with the distance from the pipe wall, the analysis for the flow in annulus is more complex than in a round tube or parallel plate channel. In this study, fully developed turbulent flow of water through a horizontal flow loop with concentric annular geometry (inner to outer pipe radius ratio = 0.4) was investigated. Reynolds number range varied from 17,700 to 66,900. Velocity near the wall region was measured using high resolution particle image velocimetry (PIV) system. Axial mean velocity profile was found to be following the universal wall law (i.e., u+ = y+) close to the wall (for y+ < 10) and log law away from the wall (y+>10). For all the cases investigated, radial positions of the maximum velocity and zero shear stress were very close to each other (± 0.5 mm). The difference between the both locations were found to be varying from 1.3 to 3.3% ( 2% on the average).
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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".