Journal of the Korea Computer Graphics Society (한국컴퓨터그래픽스학회논문지)

Korea Computer Graphics Society (한국컴퓨터그래픽스학회)
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An Adaptive FLIP-Levelset Hybrid Method for Efficient Fluid Simulation

효율적인 유체 시뮬레이션을 위한 FLIP과 레벨셋의 적응형 혼합 기법

  • Received : 2013.06.24
  • Accepted : 2013.07.30
  • Published : 2013.09.01
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Abstract

Fluid Implicit Particle (FLIP) method is used in Visual Effect(VFX) industries frequently because FLIP based simulation show high performance with good visual quality. However in large-scale fluid simulations, the efficiency of FLIP method is low because it requires many particles to represent large volume of water. In this papers, we propose a novel hybrid method of simulating fluids to supplement this drawback. To improve the performance of the FLIP method by reducing the number of particles, particles are deployed inside thin layers of the inner surface of water volume only. The coupling between less-disspative solutions of FLIP method and viscosity solution of level set method is achieved by introducing a new surface reconstruction method motivated by surface reconstruction method[1] and moving least squares(MLS) method[2]. Our hybrid method can generate high quality of water simulations efficiently with various multiscale features.

FLIP 기반의 유체 시뮬레이션은 품질에 대비 높은 효율을 자랑하기 때문에 Visual Effect(VFX)산업에 널리 사용되고 있다. FLIP 기술에서는 바다와 같은 대규모의 물을 시뮬레이션 할 때 시각적으로 중요하지 않은 물의 안쪽까지도 파티클을 할당해야 하기 때문에 보이는 파티클보다 보이지 않는 파티클의 개수가 훨씬 많은 경우에는 시뮬레이션 작업의 효율성이 떨어진다. 본 논문에서는 이러한 단점을 보완하기 위하여 레벨셋 (Level Set)과 Fluid Implicit Particle(FLIP) 기반의 유체 시뮬레이션 기법을 혼합(hybrid)한 효율적인 유체 시뮬레이션 기법을 제안한다. 파티클들을 물의 안쪽 표면 근처의 얇은 층에만 배치함으로써 사용되는 파티클의 갯수를 줄여서 결과적으로 시뮬레이션의 효율성을 크게 높일 수 있었다. 또한 [1]의 표면 재구성 기법과 moving least squares(MLS) [2] 기법을 결합한 새로운 유체 표면 재구성 기법을 적용하여 FLIP을 통해 격자(Grid) 기반 시뮬레이션에서 발생하는 수치적 소실을 줄이고 동시에 유체의 부드러운 표면을 유지할 수 있다. 본 논문의 혼합 시뮬레이션 기술은 높은 품질의 유체 시뮬레이션을 효율적으로 수행하여 다양한 규모의 유체를 표현할 수 있었다.

Keywords

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