Integrated Design Of Heat Insulation And Mechanical Loading Of Light Thin-walled Structures Base On Bionics

With the development of modern aviation and space technology, it is imperative to improve the insulation performance of the structure. The structure, under thermal and mechanical load, is required to meet the requirements of heat insulation, lightweight and high strength.The natural organisms, whose evolution keep providing us with rich inspirations on structural design and improvement, have many performances which are superior compared to artificial materials. A good example is Crysomallon squamiferum that living in deep-sea hydrothermal vents. Their unique shells are not only helpful to endure high temperatures, high pressure and acid, but also to resist predators.In this paper, Light weight and low cost configurations of thermal protection structure are developed based on the structure of the shell of C. squamiferum and topology optimization design. Integrated considering insulation and load performance, several mathematic models are established for optimizing design.1. Transient heat transfer analysis with finite element method is presented to verify the superior insulation performance of the bionic model in different boundary conditions subjected to thermal load. The results of programs, which are verified by comparing with the results of ANSYS, indicate that the arrangement ways play important roles in the insulation and load performance.2. To the layered materials'integrated design of thermal protection and load bearing, several mathematic models are established for optimizing design. In the optimization, optimal heat insulation and load performance are taken as objective functions under thermal and static load. The optimization models are solved using the genetic algorithm. Topological design of one-dimensional and two-dimensional structures under various load and boundary conditions are given.3. Material properties depending on the design requirements are usually different. If heat insulation performance is most concerned about, stiffness and strength performance could be the constraint condition. If stiffness property is most concerned about, heat insulation and strength performance could be the constraint condition. 4. Mesh-dependence of the optimal topologies are discussed by dividing the structure into different layers as 20,40 and 80. In the optimization, the weight of the structure, strength and stiffness was taken as the constraint, respectively.This thesis is funded by The National Science Foundation of China (Projects 90816025).