以CUDA架構進行地形座標系統上之三相流模式GPU計算

MODELING THREE‐PHASE DEBRIS FLOWS IN TERRAIN-FOLLOWING COORDINATE SYSTEM AND ITS GPU COMPUTATION WITH CUDA STRUCTURE

馬晴元(Ching-Yuan Ma) ； 柯奇均(Chi-Jyun Ko) ； 王福杰(Hock-Kiet Wong) ； 戴義欽(Yih-Chin Tai)

《中國土木水利工程學刊》 34卷7期 (2022/11) Pp. 597-604

https://doi.org/10.6652/JoCICHE.202211_34(7).0004

摘要

土石流災害危險評估中，其運移特性及影響範圍為探討之要點。由於土石流的組成複雜，過往的研究往往因計算的繁複而以單相流或是二相流的理論模型進行模擬計算其運移行為，所能模擬之情境有所限制，如間隙流體的黏滯性會因懸浮細顆粒的濃度改變產生顯著的變化。本研究採用地形座標上的三相流理論之數值模式，可描述濃度較高之土砂自陡坡滑入河道後，與濃度較低之河水相混合後之動態行為。模擬之結果顯示，下滑之土體不僅推移河道中之水體產生湧浪，水面上溯入侵對岸導致氾濫。此外，本研究的數值模式採用CUDA架構進行GPU高效率即時演算，深具防災工程應用情境探討的潛力。

關鍵字

三相流土石流模型 ； 地形座標系統 ； CUDA ； GPGPU

並列摘要

In terms of disaster assessment for the debris flows, the characteristics of flow behaviors and the associated flow paths are the main concerns. Despite the complex composition of debris flow, models of single-phase or two-phase approaches are employed for the purpose of reducing the computational expense. This practice has highly limited the capability of describing various scenarios because the concentration of the suspended fine clay/silt significantly influences the viscosity of the interstitial fluid. In the present study, a three-phase (solid, clay/silt, and water) model for debris flows is suggested, which is given in the terrain-following coordinate system. With this three-phase approach, the merging of high-density debris flows into the river can be well described, where a surge is induced, and the water level is enhanced together with intrusion into the opposite bank. In addition, the associated numerical model is implemented with the CUDA structure for GPU computation. The high efficiency exhibits the powerful capability of real-time calculation, yielding the impressive potential for engineering applications with respect to scenario investigation.

並列關鍵字

three-phase debris flow model ； terrain coordinates ； CUDA ； GPGPU

參考文獻

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