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REAL TIME SIMULATION OF A TORNADO

Shiguang Liu, Zhangye Wang, Zheng Gong, Lei Huang, and Qunsheng Peng

http://kucg.korea.ac.kr

ABSTRACT

simulating a tornado scene Based on Reynold-average Navier-Stokes equa-

tions. The dust particle flow is modeled by non-viscos-

ity Navier–Stokes equations Multi-Fluid Solver is designed and implemented

on GPU. Efficient method is proposed to simulate the tor-

nado’s interaction with surrounding large ob-jects.

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INTRODUCTION

RATFM is proposed to simulate the chaos ap-pearance of tornados more realistically than previous methods

A novel two-fluid system solver is designed to achieve real time simulation

To our knowledge, it is the first attempt to simulate damage from a tornado on sur-rounding objects

Our system is easy to implement. By in-putting different initial parameters, different tornado scenes can be produced automati-cally

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RELATED WORK

simulating natural phenomena smoke,water & fire semi-Lagrangian method

Mizuno volcanic clouds consist of two fluids

Müller et al. smoothed particle hydrodynamics

Losasso et al. particle level set method simulate the interactions among multiple liquids

Zhu et al. two-fluid lattice Boltzmann model

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RELATED WORK

Modeling the motion of dust particles contact force, normal force, and shear force

Ding et al. propose an approach for tornado simulation To use many particles (not real time)

Our TFM method Real-time interaction with large objects

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REYNOLD-AVERAGE NAVIER–STOKES EQUATIONS

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Interaction force

Between air flow and dust particle flow plays an important part in modeling a tornado

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Reynolds shear stress

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REYNOLD-AVERAGE TWO-FLUID MODEL

dust particle flow model

non-viscosity, incompressible fluid

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BOUNDARY CONDITIONS

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TORNADO’S CONDITIONS

horizontal velocity field : rotating

vertical velocity field : uplifting

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MODELING CONTRAST BETWEEN RATFM AND TFM (RESULTS)

RATFM

TFM

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS

Tonado 에 의해 부서지는 object 를 시뮬레이션

Object 는 voxel 에 연결 되어 있음

Voxcel 이 큰 압력을 받으면 연결된 object 부분을 부숨

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS

Object 가 받는 힘

Torque

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS (RESULTS)

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS (RESULTS)

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THE TORNADO’S INTERACTION WITH LARGE OBJECTS (RESULTS)

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MULTI-FLUID SOLVER ON GPU

Our model describes a multiple fluid system Air flow particle flows.

We solve the multiple Navier-Stokes equa-tions in parallel in one rendering pass by combining multiple field data texture into one texture. It reduces the calculating time

Flat 3D texture technique It’s easy to read and store velocity data

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MULTI-FLUID SOLVER ON GPU

Flow chart of Multi-Fluid Solver With this, we can solve

multiple NS in parallel in one rendering pass.

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MULTI-FLUID SOLVER ON GPU (RESULTS)

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RESULTS AND DISCUSSION

Successfully generated dynamic tornado scenes

Calculating the Poisson equation use the Jacobi iterative method 25 frames per second More iterations, lower frame rate

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CONCLUSION AND FUTURE WORKS

Simulating realistic tornado scenes To use RATFM

The tornado’s interaction with surrounding large objects was simulated

Future Works mixtures with three or more fluid components

Water & Oil Other phenomena