Design of thermal-anemometry-based probes for the simultaneous measurement of velocity and gas concentration in turbulent flows
Bibliographic record
Abstract
Abstract Although thermal anemometry has been employed for the simultaneous measurement of velocity and gas concentration, the underlying theory and techniques to do so are not well established. To rectify this situation, the present work uses theory and experiments to investigate the design of thermal-anemometry-based probes capable of making such measurements, specifically focusing on those for use in helium/air mixtures. It is demonstrated that an interference probe, which consists of two hot-wires placed close enough together that one is located in the thermal wake of the other, can be used to simultaneously measure velocity and helium concentration. The performance of the probe is increased when (i) the separation distance ( s ) between the wires is small ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi>s</mml:mi> <mml:mo>/</mml:mo> <mml:msub> <mml:mi>d</mml:mi> <mml:mrow> <mml:mtext>up</mml:mtext> </mml:mrow> </mml:msub> <mml:mo>≲</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:math> , where <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mi>d</mml:mi> <mml:mrow> <mml:mi mathvariant="normal">u</mml:mi> <mml:mi mathvariant="normal">p</mml:mi> </mml:mrow> </mml:msub> </mml:math> is the diameter of the upstream wire), and (ii) the downstream wire overheat ratio is low. Furthermore, a short downstream wire is recommended to ensure that the separation distance remains small while the wires are being operated.
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 distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| 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) | 0.000 | 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 teacher head, 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".