Free damping treatment for a marine life hoist of the helicopter is analyzed in this paper. Based on the pipe structure used in actual life hoist bracket, the complex rigidity method is used to analyze the damping loss factor of the pipe structure. When the temperature is 30°C and the thickness of the damping material is 2.5mm, the damping loss factor of the structure increases by 9.83 times. The damping ratio of the first mode reaches 11.61%. The results indicate that the free damping treatment can obviously increase the damping loss factor and the modal damping ratio of the structure, which can mitigate structural vibration and reduce noise induced by the vibration.

Composite material is widely used to maintain damaged structures of aircraft. The 3D finite element model of composite cement maintenance for aircraft is established by finite element method software ANSYS Workbench. The structural characteristics and usage status of the composite cement maintenance model is analyzed, and then the optimal structural parameters of the composite patch are obtained, including the length, width and thickness. The results show that the composite cement maintenance method could effectively restore the rigidity, and improve the strength of the structure. Furthermore, the optimal design for composite patch ensures safety of aircraft, economics of maintenance, and operability of repair methods.

For research on comprehensive performance of crankshaft in piston compressor, multi-body dynamics model was built to get mechanical boundary conditions of the crankshaft, and the fatigue strength was verified; Finite element model (FEM) of the crankshaft was established, and the 1st 6 modal of the crankshaft was obtained. The results showed that fatigue strength and dynamic characteristic of the crankshaft was qualified. Theoretical basis could be provided for optimize the crankshaft’s structure by fatigue strength and modal analysis.

In this paper, the key technique involved in life prediction of aeroengine’s high temperature component for creep and fatigue/creep interaction, namely, the life prediction methods for high temperature component are discussed systematically. The essential thinking、features and development direction of the theories are commented in detail. All the results obtained are valuable to engineering applications.