To solve thermal-acoustic fatigue of aero-engine thin-walled structure

the coupled finite element method/boundary element method was used to calculate dynamic response of GH188 thin-walled structures. Based on the theory of Miner liner fatigue accumulative damage

an improved rain-flow counting method and a Morrow mean stress model were adopted to estimate the fatigue life of thin-walled structures. With the use of high temperature travelling wave tube tester

GH188 thin-walled structure high temperature acoustic vibration fatigue test was conducted to obtain modal frequency

stress/strain response and fatigue life results of thin-walled structure under different temperatures and acoustic loads. It was shown in the contrastive analysis of the simulating calculation and test results that numerical simulation had accurate location judging for structural damage positions

all in the rooted positions of structures. The first-order thermal modal frequency was of consistent structures

with errors between 0.49%-2.09%

and X-stress response peaks were centered on fundamental frequency. With the rise of temperature

structure softening and stiffness reduction occurred

and response peak moved to the left; as the prediction level was consistent with the experiment

errors were between 1%-3%

validating the accuracy of thin-walled structure calculation method and model thermal-acoustic response. Structure fatigue life showed a decreasing trend with the increase of temperature and sound pressure level

and the predicted value of fatigue life and the test result were in the same order of magnitude

with the error between 3-3.5 times

satisfying the requirements of engineering level life prediction

and validating the effectiveness of simulation method for predicting thermal-acoustic fatigue life of thin-walled structure.