The Analysis And Optimization Of The Thermo-mechanical Properties For Composite Lattice Structure

The lattice truss core structures are lightweight multifunctional materials and can be designed conveniently, which are considered as the most attractive structures in the aeronautic and astronautic engineering. However, the carbon fiber composite investigated here with low thermal conductivity, so it is important to research the heat dissipation, heat transfer and structural optimization of this lattice material. In this thesis,it is by burying heat pipe in the structure to expand the area of heat dissipation so as to lower the temperature of structure.First, the equivalent thermal conductivity of heat pipe is obtained according to the principle of heat pipe. Meanwhile, the equivalent thermal expansion coefficient and elastic modulus of laminate are derived. These provide the preliminary parameter for the numerical simulation. A new theory model is proposed to evaluate the heat dissipation efficiency, which provides the theoretical guidance for the optimization of laminate in chapter three. The software ANSYS is performed to investigate the ply angle's influence on the temperature field while heat pipes are buried or not. The temperature field of different relative density of the vertical and pyramidal truss core sandwich structures is investigated in chapter four, and the temperature field is studied with the heat pipe buried too. Finally, the distribution of thermal stress is explored in the thermal load, which can be served the basis of the research for heat distortion.