Numerical Simulation on the Flow-Induced Vibration of Two Square Cylinders in Staggered Arrangement

Abstract

Abstract Based on the design of the heat transfer tube bundles with square cross section of the steam generators in the high temperature reactor-pebble bed modules (HTR-PM), the flow-induced vibration (FIV) of two single-degree-of-freedom (SDOF) square cylinders in staggered arrangement were investigated to guide the design, processing and manufacture of heat transfer components. Numerical simulation on the FIV of two square cylinders in staggered arrangement was carried out at Reynolds number Re = 100 with the mass ratio of 20. The wake structures of two square cylinders in different arrangements were analyzed. Three distinct flow regimes, i.e. one single-street modes S-I and two double-street modes T-I and T-II, are identified based on Strouhal numbers and flow structures. The amplitude and frequency of FIV response and the lift coefficient of two square cylinders at Ur = 1–30 were obtained to analyze the FIV behavior. The results show that upstream cylinder in the arrangements of mode S-Ia① and S-Ia② is prone to galloping while downstream cylinder in the arrangements of mode S-Ia③ and T-I is prone to galloping. The VIV amplitude of downstream cylinder in most staggered arrangements is much larger than that of single square cylinder while the VIV of upstream cylinder is suppressed.