Abstract
Maintaining PWR components under reliable operating conditions requires a complex design to prevent damage from flow-induced vibration, wear, etc. To improve prediction of tube/support interaction and wear in PWR components, EDF has undertaken experimental and computational studies. This paper illustrates one aspect of this program, related to contact forces between steam generator tubes and anti-vibration bars (AVBs). The dynamic, nonlinear behavior of a U-tube excited by air cross-flow is investigated on the CLAVECIN experiment. Interesting, rather unexpected results have been obtained, by varying clearances and flow velocities. Paper is focused on: (i) originality of experiment with a force measurement device located in flow; (ii) importance of a refined data processing for accurately measuring contact forces; (iii) presentation of unexpected phenomena revealed in CLAVECIN experiment, i.e. a flow-induced decentering of the tube which changed the initial tube/AVB clearance, and consequences on tube/support interaction; (iv) influence of actual tube/support clearance in flow on wear mechanisms. The work, presented in second part of this paper, concentrates exclusively on physical interpretation of flow-induced decentering phenomenon and theoretical analysis of its consequences on dynamic tube/support interaction. We show that the flow-induced decentering phenomenon can be generated by an unstable quasi-static coupling between the flexible tube
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Citation Formats
Gay, N, and Granger, S.
Flow-induced decentering and tube support interaction for steam generator tubes: experiment and physical interpretation.
France: N. p.,
1992.
Web.
Gay, N, & Granger, S.
Flow-induced decentering and tube support interaction for steam generator tubes: experiment and physical interpretation.
France.
Gay, N, and Granger, S.
1992.
"Flow-induced decentering and tube support interaction for steam generator tubes: experiment and physical interpretation."
France.
@misc{etde_10131953,
title = {Flow-induced decentering and tube support interaction for steam generator tubes: experiment and physical interpretation}
author = {Gay, N, and Granger, S}
abstractNote = {Maintaining PWR components under reliable operating conditions requires a complex design to prevent damage from flow-induced vibration, wear, etc. To improve prediction of tube/support interaction and wear in PWR components, EDF has undertaken experimental and computational studies. This paper illustrates one aspect of this program, related to contact forces between steam generator tubes and anti-vibration bars (AVBs). The dynamic, nonlinear behavior of a U-tube excited by air cross-flow is investigated on the CLAVECIN experiment. Interesting, rather unexpected results have been obtained, by varying clearances and flow velocities. Paper is focused on: (i) originality of experiment with a force measurement device located in flow; (ii) importance of a refined data processing for accurately measuring contact forces; (iii) presentation of unexpected phenomena revealed in CLAVECIN experiment, i.e. a flow-induced decentering of the tube which changed the initial tube/AVB clearance, and consequences on tube/support interaction; (iv) influence of actual tube/support clearance in flow on wear mechanisms. The work, presented in second part of this paper, concentrates exclusively on physical interpretation of flow-induced decentering phenomenon and theoretical analysis of its consequences on dynamic tube/support interaction. We show that the flow-induced decentering phenomenon can be generated by an unstable quasi-static coupling between the flexible tube and the confined flow, in the vicinity of the support system. This phenomenon is not specific to the CLAVECIN tests and it can be expected every time that a movable obstacle is subjected to confined flow. Moreover, in single-sided impacting conditions, the theoretical analysis confirms the linear relation, found in the CLAVECIN tests, between the mean impact force and the static lift force associated with (Abstract Truncated)}
place = {France}
year = {1992}
month = {Nov}
}
title = {Flow-induced decentering and tube support interaction for steam generator tubes: experiment and physical interpretation}
author = {Gay, N, and Granger, S}
abstractNote = {Maintaining PWR components under reliable operating conditions requires a complex design to prevent damage from flow-induced vibration, wear, etc. To improve prediction of tube/support interaction and wear in PWR components, EDF has undertaken experimental and computational studies. This paper illustrates one aspect of this program, related to contact forces between steam generator tubes and anti-vibration bars (AVBs). The dynamic, nonlinear behavior of a U-tube excited by air cross-flow is investigated on the CLAVECIN experiment. Interesting, rather unexpected results have been obtained, by varying clearances and flow velocities. Paper is focused on: (i) originality of experiment with a force measurement device located in flow; (ii) importance of a refined data processing for accurately measuring contact forces; (iii) presentation of unexpected phenomena revealed in CLAVECIN experiment, i.e. a flow-induced decentering of the tube which changed the initial tube/AVB clearance, and consequences on tube/support interaction; (iv) influence of actual tube/support clearance in flow on wear mechanisms. The work, presented in second part of this paper, concentrates exclusively on physical interpretation of flow-induced decentering phenomenon and theoretical analysis of its consequences on dynamic tube/support interaction. We show that the flow-induced decentering phenomenon can be generated by an unstable quasi-static coupling between the flexible tube and the confined flow, in the vicinity of the support system. This phenomenon is not specific to the CLAVECIN tests and it can be expected every time that a movable obstacle is subjected to confined flow. Moreover, in single-sided impacting conditions, the theoretical analysis confirms the linear relation, found in the CLAVECIN tests, between the mean impact force and the static lift force associated with (Abstract Truncated)}
place = {France}
year = {1992}
month = {Nov}
}