EVALUATION METHOD FOR INDEPENDENT VIBRATION TUBE

PROBLEM TO BE SOLVED: To obtain a method for evaluating stress generated in a heat transfer tube (independent vibration tube) independently vibrating in an in-plane direction when exciting force is applied to a heat transfer tube group.SOLUTION: An evaluation method for an independent vibration tube comprises the steps of: calculating a first response displacement amount according to exciting force of one heat transfer tube out of a heat transfer tube group including a plurality of heat transfer tubes without taking interaction with the other heat transfer tubes other than the one heat transfer tube out of the heat transfer tube group into account; calculating a response displacement amount of a whole tube group including the other heat transfer tubes according to the exciting force; calculating a contact load due to collision between the one heat transfer tube and an adjacent heat transfer tube adjacent to the one heat transfer tube out of the heat transfer tube group on the basis of the first response displacement amount of the one heat transfer tube and the response displacement amount of the whole tube group; calculating a second response displacement amount according to the exciting force of the one heat transfer tube on the basis of the contact load received from the exciting force and the adjacent heat transfer tube; and calculating stress generated in the one heat transfer tube on the basis of the second response displacement amount.SELECTED DRAWING: Figure 5 【課題】伝熱管群に加振力が作用した際、面内方向に独立して振動する伝熱管（独立振動管）に発生する応力を評価する方法を得る。【解決手段】複数の伝熱管を含む伝熱管群のうち一の伝熱管の前記加振力に応じた第１応答変位量を、前記伝熱管群のうち前記一の伝熱管以外の他の伝熱管との相互作用を考慮せずに算出するステップと、前記加振力に応じた前記他の伝熱管を含む管群全体の応答変位量を算出するステップと、前記一の伝熱管の前記第１応答変位量と前記管群全体の応答変位量とに基づいて、前記一の伝熱管と、前記伝熱管群のうち前記一の伝熱管に隣接する隣接伝熱管との間の衝突による接触荷重を算出するステップと、前記加振力および前記隣接伝熱管から受ける前記接触荷重に基づいて、前記一の伝熱管の前記加振力に応じた第２応答変位量を算出するステップと、前記第２応答変位量に基づいて、前記一の伝熱管に発生する応力を算出するステップと、を備える。【選択図】図５