Physically Based Realistic Simulation Of Fluid-Solid Coupling And Deformation-Destruction

Fluid-solid coupling and deformation-destruction are common natural phenomena in film special effects and video games.How to generate realistic,interactive and real-time computer animations for the phenomena has always been a research hotspot in the field of computer graphics.Physically based simulation can produce realistic simulation effects based on the physical mechanism behind the phenomenon,so it has received extensive attention in the field of computer animation.But when dealing with complex materials(such as anisotropic materials,porous media)and coupling phenomena,physically based simulation suffers from complex model,poor system robustness,difficult interaction and time-consuming computation,which brings great challenges for the simulation of fluid-solid coupling and deformation-destruction phenomena.Considering about the above difficulties,this thesis proposes a series of physically based realistic simulation methods for representative fluid-solid coupling and deformation-destruction phenomena via deep exploration of complex movement model and physical principle behind the fluid-solid coupling and deformation-destruction phenomena.The main contributions of this paper include:· We propose a simulation algorithm for seepage-structure coupling phenomenon of porous media based on particle finite element method.To solve the problem that traditional finite element method is unstable when dealing with large deformations,we adopt smooth parti-cle hydrodynamic model to track the free moving particles,and calculate control equation on generated particle finite element mesh to ensure the robustness of the simulation algorithm.Then surface can be reconstructed according to link information and adaptive Alpha Shape,thus we can simultaneously deal with many complex phenomena such as seepage, structural deformation and fracture of porous media,and achieve the realistic simulation of pore seepage and deformation-destruction in porous media.· We propose a simulation algorithm for multi-physics lava-mountain coupling phenomenon based on smooth particle hydrodynamic method.The method analyzes and simplifies the physical model of complex multi-material and multi-physics volcanic phenomena rationally,and establishes a dynamic coupling model for the multi-physics processes by combining the thermodynamic model.Then we solve the above model rapidly based on smooth particle hydrodynamics method,in this way we can deal with the complex coupling phenomena such as heat transfer and phase transition between lava,volcanic rock,mountain and smoke simultaneously,and realize rapid realistic simulation of large-scale volcanic scene.· We propose a smoke-solid coupling simulation algorithm based on Euler method and deep learning method.To overcome the time-consuming defects in desgin of high-resolution smoke simulation,the method constructs massive training data set with smoke-solid coupling simulation through Euler method,and trains convolutional neural network for parameter estimation to calculate physical parameters of Eulerian model with high precision.Then the learnt physical parameters are used as prior knowledge for low-resolution input generated by user design,and high-resolution velocity field is generated by convolution neural network considering physical constraints.Thus we achieve a rapid smoke-solid coupling simulation with rich detail.· We propose a simulation algorithm for brittle fracture of anisotropic materials based on adaptive smooth particle hydrodynamics method.Aiming at the complex physical parameters and difficult interaction of anisotropic materials,this method simplifies the stress analysis of anisotropic materials and improves the accuracy and stability of the algorithm by tracing stress in different directions through anisotropic kernels.According to the result of stress analysis,we design a user-controllable crack generation mode and an adaptive particle model via geometric subdivision to reconstruct the realistic crack surface correctly. Finally a rapid realistic simulation of brittle fracture of anisotropic materials is realized.In this paper,the realistic results of above simulations are rendered with physically based rendering engine.A large number of experimental results verify the validity and practicability of the proposed method.