| The fluidelastic instability of tube arrays and flow induced vibration are studied systematically in this dissertation. Its contents include:(1) A new mathematical model is proposed for the fluidelastic instability analysis of tube arrays. This model can describe all-sidely the instability mechanism and coefficients needed in computation can be got from quasi—static experiment, so it has advantage over models currently in use.(2) Based on the model, computational method about the critical velocity of straight tube arrays is given. The critical velocity for both triangular and square straight tube arrays are discussed and computational results coincide well with the test results and computational results based on the unsteady flow theory.(3) Critical velocity of U-tube arrays is analysised for the first time, the computational method and the calculating formulas are given.(4) The influence of inactive supports on critical velocity is discussed thoroughly and a pratical probabilistic method is put forward to estimate fluidelastic instability of inactive support tube.(5) Numerical simulation of turbulence and fluidelasticity induced vibration and prediction of tube wear rate is developed. Computational and iterative formulas based on the finite element method are given.(6) Programs, AFITA and SHET, are developed, which can be used to compute the critical velocity for straight tube arrays and U-tube arrays of all sorts of tube arrangements in uniform and non—uniform flow and to calculate the response of tube due to flow induced vibration.(7) Base on the results of computation and experiment at home and abroad, A modified and complementary proposal is presented for the computation of critical velocity of 《Steel tubular heat exchanger》 published by the China National Standard Comission of Pressure Vessel.
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