Coupling Analysis Of Ablation And Temperature Field Of C/C Composite Based On Peridynamics

In the aerospace field,aircraft is often confronted of high temperature,high pressure and high stagnation in the harsh working conditions when crossing the atmosphere.Excessive heat will cause the internal structure of the aircraft to be burned.In order to ensure the safe use of the structure and predict the service life of the structure,it is necessary to analyze the ablation and thermal response of the C/C composite under constant thermal load and study its ablation mechanism.With the rapid development of computer technology,and the special nature of ablation,the advantages of numerical simulation have become more prominent.At the same time,due to the existence of the boundary movement problem of ablation problem,it is difficult to adopt the traditional classical methods based on continuous hypothesis,such as finite element method and finite difference method.Peridynamics theory uses differential-integral equations to establish basic equations.It does not use continuity assumptions,so it is more suitable for solving non-continuous problems such as cracks,explosions,ablation,and corrosion.Based on this,the peridynamics is used to simulate the ablation process of C/C materials under constant thermal loading conditions.The main research contents and results are as follows:1.Using a thermochemical ablation theory that describes the ablation of C/C composites,combined with the improved non-ordinary state based peridynamics transient heat transfer equation,a peridynamics heat transfer theory based on thermochemical ablation is proposed,and the natural description of ablation boundary movement is realized without introducing other complicated conditions.2.Based on the basic equations describing the thermo-chemical ablation problem,the corresponding calculation format is derived,the calculation process analysis is completed,the flow chart is generated,and the simulation program of thermo-chemical ablation is written in FORTRAN language;Numerical simulations are carried out by referring an example in a literature,and the results are in good agreement with the experimental results in the literature.3.Using the above peridynamics heat transfer theory based on thermochemical ablation of C/C composites,we study the influence of different neighborhood radius and different particle spacing on the numerical results.Numerical simulation of stress field of C/C composites due to ablation caused by boundary movement is implemented,and the influence of boundary motion on the stress field of the model during ablation is described.