Research On Multi-detail And Parallel Fluid Simulation Based On Particle-grid Hybrid Method

Physics-based real-time fluid simulation is one of the important research directions of computer graphics.It has been widely used in computer animation games,movie special effects,industrial simulation,military simulation,and popular science education.With the increasing demand for fluid animation,how to generate realistic animation effects and how to quickly simulate has become an important research direction in the current academic world.Starting from solving the problems of fidelity and real-time simulation,this paper focuses on the method of enhancing multi-detail and fast simulation of fluid animation,and designs a multi-detail and real-time simulation method based on particle-grid hybrid method.In order to achieve multi-detail and realtime fluid simulation,this paper starts discussion and research based on the LBM-VOF method.It implements multi-detail fluid simulation from two aspects of detail protection and detail enhancement,and accelerates fluid solution and fluid rendering through GPU.Through experimental comparison,the method in this paper has made breakthroughs in three aspects: detail protection,detail enhancement,and real-time simulation and rendering.The specific research contents and innovations are summarized as follows:1.A reconstruction method of gas grid distribution function with second-order accuracy is proposed.This method mainly solves the problem of low accuracy of the gas cell distribution function reconstruction method in the LBM-VOF method.The core idea is to first expand the distribution function by the Chapman-Enskog method,and divide the distribution function into equilibrium distribution functions and nonequilibrium functions.The two parts of the state distribution function are approximated by the equilibrium state distribution function and the non-equilibrium state distribution function according to the related theory of the BGK model.Since the method is calculated by the related theory of the BGK model,the method has the same second-order accuracy as the BGK model.The experimental results show that the reconstruction accuracy of this method is higher than that of LBM-VOF method,and it also improves the accuracy of free surface tracking to a certain extent,thereby achieving the protection of the details of the fluid surface.2.A method of detail enhancement based on particle-grid coupling is proposed.This method mainly solves the problem of anomalous interface grids in the LBM-VOF method.The core idea is to use particles to replace the anomalous interface grids to evolve.The full advantage of the grid method to solve the precise velocity field and the particle method are good at representing the details of fluid surfaces The advantage of this method is that the particles and the grid are organically combined by the two-way coupling model in this paper.The experimental results show that the method can solve the abnormal interface grid on the premise of ensuring the physical conservation of the fluid system,and enrich the surface details of the fluid to a certain extent,thereby achieving the purpose of detail enhancement.3.Designed GPU-based real-time fluid simulation and rendering methods.This method mainly solves the fluid solution pressure and fluid rendering bottleneck caused by large-scale fluid simulation.For fluid solution,this paper designs a series of highperformance algorithms based on algorithm characteristics and GPU architecture characteristics,and improves GPU-based screen space rendering method makes this rendering method fit well with the method in this paper.The experimental results show that the GPU-based real-time fluid simulation and rendering method designed in this paper can effectively accelerate the algorithm and improve the rendering effect,so as to achieve real-time fluid simulation and rendering.