A study on improving the computational efficiency of debris flow numerical models using dynamic grid activation method

Taeun Kang; Minseok Kim; Hyunuk An; Seungsoo Lee

doi:10.3741/JKWRA.2025.58.11.965

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2025 Vol.58, Issue 11 Next Page

Research Article

A study on improving the computational efficiency of debris flow numerical models using dynamic grid activation method 동적 격자 활성화 기법을 활용한 토석류 수치모형의 계산 효율 향상 연구

30 November 2025. pp. 965-976

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Abstract

Due to the recent increase in the frequency of localized heavy rainfall, the occurrence of landslides and debris flows has been rising nationwide, highlighting the need for accurate prediction and proactive response measures. To address this, scenario-based predictions for hazard mapping are essential, and a balance between computational efficiency and spatial resolution must be achieved. This study proposes a Dynamic Grid Activation technique that selectively activates computational cells based on the presence or potential of active flow during simulation. By excluding areas unrelated to debris flow, unnecessary computations are significantly reduced. To evaluate the effectiveness of the proposed method, four simulation scenarios were compared: (1) full-domain computation, (2) full-domain parallel computation, (3) dynamic grid activation based on active flow, and (4) dynamic grid activation combined with parallel computation. These scenarios were applied to an actual debris flow event for comparison. Results show that the dynamic activation with parallel computation achieved identical simulation accuracy to the conventional method while improving computation speed by up to 3.49 times. Therefore, the proposed method is expected to significantly enhance the computational efficiency of debris flow models, enabling faster prediction and more effective parameter calibration.

Keywords

Dynamic Grid Activation method (DGA)

Dynamic domain filtering

Computational efficiency

Debris flow simulation

최근 빈번한 국지성 폭우로 인한 산사태 및 토석류의 발생 빈도가 전국적으로 증가함에 따라, 이에 대한 정확한 예측 및 선제적 대응 방안 마련의 필요성이 커지고 있다. 이를 위해서는 다양한 시나리오 기반의 사전 모의를 통한 위험지도 작성이 요구되며, 예측 모형의 계산 효율성과 해상도 간의 균형 확보가 중요하다. 본 연구에서는 활성흐름 기준으로 계산 도메인을 동적으로 활성화하는 동적 격자 활성화 기법을 제안하고, 해당 기법의 계산 효율 향상 효과를 분석하였다. 제안된 방법은 활성흐름이 존재하거나 거동 가능성이 있는 격자만을 계산에 포함하고, 토석류 이외 지역은 제외함으로써 불필요한 연산을 줄인다. 이를 검증하기 위해 (1) 전체 도메인을 계산하는 기존 방식, (2) 전체 도메인을 병렬 계산하는 방식, (3) 모의 중 활성흐름 분포에 따라 격자를 동적으로 활성화하는 방식, (4) 모의 중 활성흐름 분포에 따라 격자를 동적으로 활성화하는 동시에 병렬계산을 수행하는 4 가지 주요 시나리오를 혼합해 실제 토석류 피해지역에 적용하여 비교‧분석하였다. 그 결과, 모의 중 활성흐름 분포에 따라 격자를 동적으로 활성화하는 방식과 병렬계산을 병행한 방식이 기존 방식의 모의결과와 값이 동일하면서도 최대 3.49배 정도 계산 속도가 증가한 것으로 나타났다. 따라서 본 연구에서 개발한 동적 격자 활성화 기법을 토석류 해석 모형에 적용시 계산 효율을 실질적으로 향상시켜 빠른 예측과 매개변수 보정 등을 수행할 수 있을 것으로 기대한다.

키워드

동적 격자 활성화 기법

동적 도메인 필터링

계산 효율 향상

토석류 수치모형

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Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 58
No :11
Pages :965-976
Received Date : 2025-08-27
Accepted Date : 2025-09-23
DOI :https://doi.org/10.3741/JKWRA.2025.58.11.965

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

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