Modelling of fluidelastic vibrations of heat exchanger tubes with loose supports

• Published in: Nuclear engineering and design Vol. 238; no. 10; pp. 2507 - 2520
• Main Authors: Hassan, M., Hayder, M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2008; Elsevier
• Subjects: Applied sciences; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels; Turbulence; Tube; Vibration; Critical flow; Heat exchanger; Wear; Instability; Flow velocity; Modeling; Steam generator; Nuclear reactor
• ISSN: 0029-5493
• DOI: 10.1016/j.nucengdes.2008.05.014

The existence of gaps at tube supports necessitates time domain modelling of fluid forces to predict flow-induced vibrations and associated wear in heat exchangers and steam generators. This paper presents a new time-domain model for fluidelastic instability forces of tubes with loose-supports. In this model, the fluidelastic force, which is dependent on flow velocity and array geometry, is superimposed on the turbulence forcing function. The model was used to calculate the critical flow velocity, tube response, and tube/support interaction parameters, such as impact force and work rate. The critical velocity for linear cases was accurately predicted. The critical flow velocity for the loose support case was found to be sensitive to both the gap size and the turbulence level.