Comparison of Design Criteria for Flow-induced Vibration of Heat-exchange Tube

The steam generator is an important device in the nuclear reactor to transfer the heat of the primary circuit to the secondary circuit (water-steam power circuit). The heat-exchange tube vibration caused by the secondary side fluid flushing is one of the main causes of tube wall fatigue, wear and tear. In order to ensure the structural integrity of the heat-exchange tube, it is necessary to carry out flow-induced vibration design and evaluation of the heat-exchange tube. For the design and evaluation of flow-induced vibration of a cylindrical structure such as a heat-exchange tube, there are three design codes including GB/T151, TEMA and ASME. The comparison of the design criteria for flow-induced vibration of heat-exchange tubes in three design codes was made, and the differences in the calculation of relevant criteria and parameters and the difference in the determination of the mechanism related to flow-induced vibration were pointed out. A typical heat exchanger was selected as an example to demonstrate the similarities and differences between the three design codes for the flow-induced vibration evaluation of heat-exchange tubes. The deviations of the calculation results of characterizing the characteristic parameters of flow-induced vibration (such as additional mass, natural frequency, vortex shedding frequency, amplitude, etc.) were given for the selection of different design criteria of codes, and the reference suggestions for the conservativeness of the three design codes in engineering applications were pointed out. The results show that for different parameters, the design codes are not the same in conservative property. The calculation of frequency based on TEMA is relatively more conservative. The other parameters in GB/T151 are more conservative. TEMA and ASME are more tolerant than GB/T151.