## 6 Conclusions  
A methodology was developed to determine the fatigue life or residual strength of composite panels subjected to combined thermal-acoustic loadings. Two features of this problem, large mean stresses and high alternating stresses, make it more complex than the fatigue of structures subjected to acoustic loading alone. The effects of the thermal environment on the dynamical properties of panels and the material properties of this material are taken into account. The static strength, residual strength, and fatigue life of the material are the input of the methodology. The methodology is validated with the residual strength test of 2D plain-woven C/SiC composite panel subjected to combined thermal-acoustic loadings. It has been shown that the results of residual strength predicted by the methodology are well correlated with the experimental results, and are conservative compared to experimental results. Conceptualization, Y.S. ; Resources, Y.L. ; Writing--review & editing, Y.Z. All authors have read and agreed to the published version of the manuscript. This study is supported by the National Natural Science Foundation of China (No. 11602073). Not applicable. Informed Consent Statement: Informed consent was obtained from all subjects involved in the study. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{5}{c}{**Tensile Residual/MPa**} \\ \hline
**Series** & **Experimental** & **Mean Value** & **Standard** & **Simulation** & **Error/\%** \\
**Number** & **Result** & **Mean Value** & **Deviation** & **Result** & **Error/\%** \\ \hline E02 & 274.84 & & & & \\ \hline E11 & 236.59 & & & & \\ \hline E13 & 241.62 & & 248.65 & 17.62 & 231.74 & 6.80 \\ \hline E22 & 241.55 &  
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