Simulation Of Smoke Based On Physical Model

In computational fluid dynamics and computer graphics,the simulation of fluids in natural phenomena has been a hot and difficult area of research in the field.Currently,scholars have been able to realistically simulate objects with regular shapes,such as benches,water glasses and houses,but it is difficult to combine real-time and realistic simulation of fluid objects with complex and amorphous shapes,so the need to improve real-time and realistic simulation of fluid objects has become a challenge and a flash issue in computer graphics.The simulation of the motion of a fluid like smoke is extremely complex,and there are still many difficulties to be solved,including the following three main categories: one is the construction of the smoke model,that is,when the smoke simulation,the selection of the model directly affects the computational efficiency of the smoke simulation,how to select the appropriate smoke model is the primary consideration when studying smoke simulation;the second is the system real-time problem,real-time is necessary to The third is the realism of the effect,the realism of the smoke has an important impact on the visual effect,realistic smoke to achieve immersion in order to have practical significance for the operator.Therefore,the need to balance realism and real time has been a pressing challenge in the field of fluid simulation.To address these issues,this paper focuses on the physical model-based smoke simulation research and demonstrates the theoretical basis for the implementation of the method,the construction of the physical model of smoke and the real-time rendering of smoke,doing the following:Firstly,in order to solve the instability of the Eulerian method due to the large time step and the poor simulation efficiency of the Lagrangian method due to the large number of particles,this paper proposes a real-time smoke simulation method based on an improved semi-Lagrangian method,which physically models the smoke using the N-S(Navier-Stokes)equation based on the N-S equation.The method is based on physical modelling,so the motion effect is more realistic compared to the particle method.In order to simplify the computational effort of the numerical simulation,and considering that the viscous effect of the smoke fluid is negligible with a coarse grid,the incompressible and inviscid N-S equation is proposed to represent the basic physical model of the smoke,and then the smoke simulation space is discretized into a number of grids based on the semi-Lagrangian method,and these grids are then set up as individual particles,which makes the smoke motion The second method is to use the traditional solution to solve the smoke simulation.The Helmholtz-Hodge method is used to decompose the simplified N-S equation into advection,external force,diffusion and projection terms.The solution is then solved separately.Solving advection terms by the MC method,which streamlines the computational process and introduces a vorticity-limiting term to add the small-size rolling characteristics that are lost during the numerical solution process,thus achieving a more realistic smoke.Finally,for the rendering accuracy of the smoke,this paper visualises the motion of the smoke based on an improved light projection algorithm to obtain the motion of the smoke over time,resamples the sampling points by trilinear interpolation to produce a higher quality image,and proposes the use of light advance termination to effectively eliminate the accumulation of non-essential sampling points.The algorithm proposed in this paper is a significant improvement over traditional physical models for simulating smoke effects.