Experimental Study of Dynamic Interaction Between a Steam Generator Tube and an Anti-Vibration Bar
Notice bibliographique
Résumé
A first experimental work was previously carried out to study the dynamic behavior of a tube simply supported at both ends in interaction with an anti-vibration bar at mid-span. This paper presents modifications to the previous setup with the aim of improving the accuracy of the results. A comparison of the dynamic behavior of the tube is made between both setups. The objective of this experimental study is to characterize the vibration behavior of U-tubes found in steam generators of nuclear power plants. Indeed, two-phase cross-flow in the U-tubes section of steam generators can cause many problems related to vibration. In fact, flow-induced vibration of the U-tubes can cause impacts or rubbing of the tubes against their flat bar supports. Variation of the clearance between the AVB and the U-tubes may lead to ineffective supports. The resulting in-plane and out-of-plane motions of the tubes are causing fretting-wear and impact abrasion. In this study, the clearance between the tube and the AVB, as well as the amplitude, form and frequency of the excitation force are controlled parameters. The first two modes of the tube are studied. The modifications made to the setup lead to significant improvements in the results. The natural frequencies of both setups are compared to theoretical values. The difference between experimental and theoretical frequencies confirms that the new setup better represents the theoretical model of a simply supported tube. The damping of both setups is also compared to values found in literature. The results show that the new setup is more representative of realistic steam generator situations. Compared to the first setup, the displacements of the new setup clearly indicate that the movement of the tube is mostly parallel to the flat bar and in the same direction as the excitation force. The whirling motion of the tube is prevented in the new setup. The accuracy of the contact force as a function of clearance was also improved. The use of more sensitive force sensors helped to reduce the noise level of the contact force. Finally, the dynamic interaction between the tube and the AVB, defined by the fretting wear work-rate, presents a more consistent behavior. The maximum work-rate occurs when the tube is excited around the second mode for clearance between −0.10 and 0.00 mm. Such clearance between the tube and the AVB should then be avoided to minimize fretting damage.
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 | 0,000 |
| 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 | 0,000 |
| 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 ».