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High Mach flight has put forward more stringent requirements for the material and structure design of new generation of high-speed vehicles. This paper reviews the application of ceramic matrix composites（CMCs） in the structural design of aircraft from the aspects of selection，application，and evaluation，and then the future development direction is put forward to provide reference for aircraft ceramic matrix composite structure design. The selection criteria and corresponding preparation methods of CMCs in different application scenarios are comprehensively reviewed，the typical applications of CMCs in aircraft structures are systematically introduced，and the evaluation criteria and ground test methods of the materials under near-service conditions are analyzed. To order to meet the future demands of aircraft，it is necessary to integrate computer-aided optimization technology and innovative preparation methods to enhance the temperature resistance and fatigue performance of CMCs. Developing highly reliable，long-life joining techniques and integrated design solutions will fully leverage the advantages of these materials. Additionally，in-situ characterization techniques under multi-physical field coupling need to be developed to obtain the performance evolution behaviour of CMCs in actual use，providing a reliable basis for the lightweight structural design of aircraft.

Aiming to solve the complicated problem about the coupling effect of aerodynamic force and heat for hypersonic vehicle, one-way coupling was applied to decouple the environmental load. Then, the distribution of aerodynamic force and heat of a typical composite wing under the flight situation of Mach 5 to Mach 8 was studied by finite element analysis. Based on the classical flutter theory, the critical flutter boundary was obtained. The results show that flutter phenomenon is caused by first-order bending-torsional coupling. Considering the fabricability of the composite wing, the aerothermoelastic tailoring design of composite wing under typical flight situation was carried out. In the optimal process, static intensity and thermal flutter velocity are considered as the constraints, and the optimization target is to obtain minimum mass. For approaching the best structural dynamic characteristics and aeroelastic effect, the bending-torsional coupled stiffness of the composite structure is regulated through changing layers, paving angles and laying sequence. Based on C/C ++ open source environment, a software called Aero-Opt was developed to construct an independent-industrialized analysis platform, and the aerothermoelastic tailoring research of the composite wing under most severe aerodynamic heating condition was carried out. After optimization, the thermal flutter boundary of the composite wing is improved by 22.4%, while its mass is reduced by 15.76% . [ABSTRACT FROM AUTHOR]

Based on the long short-term memory (LSTM) neural network, an identification method is proposed to identify the support stiffness of an aero-engine at rotating state. First, the dynamic model of a whole aero-engine with nonlinear support was established. The displacement responses corresponding to different support stiffnesses at the target rotating speed were obtained. Then, the deep leaning neural network with LSTM as the core layer was established. The network was trained with the displacement responses as the inputs and the support stiffnesses as the outputs. The nonlinea relationship between the support stiffnesses and the displacement responses was constructed. Finally, the support stiffness was directly identified with the generalization of the deep leaning network. The support stiffness of an aero-engine was identified by the proposed method. Results show that the recognition error is less than 2%, and the recognition accuracy of LSTM is better than that of the radial basis function neural network and support vector machine. The proposed method can avoid the complex optimization process in inverse dynamic problems and realize the identification of dynamic parameters for complex nonlinear structures. [ABSTRACT FROM AUTHOR]