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According to the actual size and the production process parameters of the large condenser in a PTA plant, obtaining a reasonable simplified model, using the software of computational fluid dynamics-Fluent, this paper has researched in the different velocity of different bundle tubes, then with reference to GB151-1999, getting a theoretical calculation of the bundle Flow-induced vibration, determined whether the condenser budle flow-induced vibration occurred.The research work mainly has covered followings:First,accoding to the technological parameters of the condenser, the reasons that which may induce vibration were analyzed. The main reasons include liquid elastic instability, vortex shedding and turbulent buffeting.Second, according to the actual size of the condenser, using a reasonable simplified modeling; determining the boundary conditions, material properties and operating conditions; formulating the solution method; analysing the flow field and finding the location and the value of the maximum velocity in different bundle tubes.Third,according to GB151-1999, the excitation frequency and critical velocity are calculated.Finally,according to the vibration criteria, it has also conducted calculation,comparison and reached a definite conclusion.Based on the above analysis, it has concluded that the import flow is smaller, the velocity is lower and the model is in single-phase, and only the several rows of tubes near the import have a more significant velocity fluctuation.The flow-induced vibration does not occur.This paper also discusses whether the simplification that fourΦ19 tubes changing into oneΦ38 tube is reasonable, based on the similarity theory, establishing two similar models, obtaining the two kinds of flow patterns.To ensure safe operation and prevent the occurrence of significant vibration on the heat exchangers and chemical equipment, this paper is of a certain theoretical and practical significance.
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