Exploring wall heat transfer characteristics in the inverted annular/slug film boiling regimes by direct hot-patch technique+
Notice bibliographique
Résumé
• Quasi steady-state subcooled film boiling experiments were conducted with water. • Wall heat transfer characteristics of the IAFB and ISFB regimes were investigated. • Void fraction data were acquired to understand heat transfer and flow characteristics. • A parametric study revealed the effects of key parameters on wall heat transfer. • Local subcooling in subcooled regime, and the mass flux and pressure in saturated regime significantly affect wall heat transfer. Inverted annular film boiling (IAFB) and inverted slug film boiling (ISFB) are highly complicated two-phase phenomena exhibiting considerable uncertainties in predicting the wall heat transfer characteristics due to lack of comprehensive experimental data and understanding on the underlying mechanisms resulting from challenging experimental conditions. Therefore, in this study, a series of quasi steady-state IAFB/ISFB experiments has been conducted using a direct hot-patch technique to improve our understanding of the wall heat transfer characteristics in these post-critical heat flux (post-CHF) regimes. Experimental conditions include the inlet subcooling up to 30 °C, mass flux between 150 and 450 kg/m 2 -s, and system pressure varying from 25 to 60 psia (0.172 to 0.412 MPa) to explore quantitative relationships between the wall convective heat transfer coefficient in the IAFB/ISFB regimes and the variables of the liquid subcooling, mass flux, and system pressure. Detailed test section wall temperature measurements are acquired using thermocouples while the void fraction and flow topology are measured via an X-ray radiography system and a gamma densitometry. In addition, analyses are carried out using a computer code for film boiling based on a one-dimensional two-fluid model. The predictive capability of the code is validated using the void fraction data obtained by radiation-attenuation techniques. The physical mechanisms are identified to explain how the key variables affect the wall heat transfer variations in the IAFB/ISFB regimes. In subcooled conditions, the wall convective heat transfer coefficient is solely determined by the local subcooling, as it is governed the interfacial heat transfer and heat conduction through the vapor film. In saturated conditions, the wall heat transfer in both the IAFB and ISFB regimes increases with increasing mass flux and system pressure because convection in the vapor phase and interfacial area concentration, respectively, dominate the heat transfer process. The acquired IAFB/ISFB data including the void fraction and flow topology, and identified physical mechanisms based on the comprehensive data are expected to help improve the predictive capability of post-CHF heat transfer in light water reactor system-level thermal–hydraulic analysis codes.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».