为研究泥石流与刚性防护结构的作用,使用耦合的离散元方法和计算流体力学方法（CFD-DEM）,分别模拟单相流和两相流对刚性防护结构的冲击。计算结果表明：单相流以堆积机制为主,而两相流表现出爬升机制;两相流中由于液体的拖曳和浮力作用,颗粒内部的接触数减少,能量耗散降低,导致颗粒的爬升高度和最大冲击力分别增加426%和488%。
Abstract
Debris flow is an extremely dangerous natural hazard, which routinely destroys wind farms in mountainous terrains. To intercept this hazardous phenomenon, rigid barriers are commonly installed in mountainous regions to mitigate the hazard of debris flow. In order to study the impact of debris flow on a rigid barrier, this paper presents a coupled Discrete Element Method and Computational Fluid Dynamics approach. This approach compares the interactions between single- and two-phase flows and a rigid barrier. The results show that the single-phase flow exhibits a predominant pile-up mechanism, while the two-phase flow in this study show a distinct run-up mechanism. Compared to the single-phase flow, due to the drag and buoyancy effect of water, the number of contacts inside particles is reduced, and less energy is dissipated. Correspondingly, the run-up height and maximum impact force of granular system increases by 426% and 488%, respectively.
关键词
陆上风电场 /
数值模拟 /
流固耦合 /
泥石流 /
防护结构 /
冲击
Key words
onshore wind farm /
computer simulation /
fluid structure interaction /
debris flow /
rigid barrier /
impact
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参考文献
[1] KOO R C H, KWAN J S H, LAM C, et al. Backanalyses of geophysical flows using 3-dimensional runout model[J]. Canadian geotechnical journal, 2017, 55(8): 1081-1094.
[2] 肖思友, 苏立君, 姜元俊. 碎屑流冲击柔性网的离散元仿真研究[J]. 岩土工程学报, 2019, 41(3): 526-533.
XIAO S Y, SU L J, JIANG Y J.Numerical investigation on flexible barriers impacted by dry granular flows using DEM modeling[J]. Chinese journal of geotechnical engineering, 2019, 41(3): 526-533.
[3] 宋东日, 周公旦, CHOI C E, 等. 土工离心机模拟泥石流问题的相似性考虑[J]. 岩土工程学报, 2019, 41(12): 2262-2271.
SONG D R, ZHOU G D, CHOI C E, et al.On the scaling principles of debris flow modeling using geotechnical centrifuge[J]. Chinese journal of geotechnical engineering, 2019, 41(12): 2262-2271.
[4] LI X Y, ZHAO J D.Dam-break of mixtures consisting of non-Newtonian liquids and granular particles[J]. Powder technology, 2018, 338: 493-505.
[5] FELICE R D.The voidage function for fluid-particle interaction systems[J]. International journal of multiphase flow, 1994, 20(1): 153-159.
[6] KAFUI K D, THORNTON C, ADAMS M J.Discrete particle-continuum fluid modelling of gas-solid fluidised beds[J]. Chemical engineering science, 2002, 57(13): 2395-2410.
[7] ZHOU Z Y, KUANG S B, CHU K W, et al.Discrete particle simulation of particle-fluid flow: model formulations and their applicability[J]. Journal of fluid mechanics, 2010, 661: 482-510.
[8] STOKES G G. On the theories of internal friction of fluids in motion and of the equilibrium and motion of elastic solids[J]. Transactions of the Cambridge Philological Society, 1844, 8(9): 287-319.
[9] ZHAO J D, SHAN T.Coupled CFD-DEM simulation of fluid-particle interaction in geomechanics[J]. Powder technology, 2013, 239: 248-258.
[10] CHOI C E, AU-YEUNG S C H, NG C W W, et al. Flume investigation of landslide granular debris and water runup mechanisms[J]. Géotechnique letters, 2015, 5(1): 28-32.
[11] ZHANG S C, HUNGR O, SLAYMAKER O.The calculation of impact force of boulders in debris flow[M]. Beijing: Science Press, 1996: 67-72.
[12] SONG D, CHOI C E, NG C W W, et al. Load-attenuation mechanisms of flexible barrier subjected to bouldery debris flow impact[J]. Landslides, 2019, 16(12): 2321-2334.
[13] FONSECA J, SIM W W, SHIRE T, et al.Microstructural analysis of sands with varying degrees of internal stability[J]. Géotechnique, 2014, 64(5): 405-411.
[14] SONG D, ZHOU G G D, XU M, et al. Quantitative analysis of debris-flow flexible barrier capacity from momentum and energy erspectives[J]. Engineering geology, 2019, 251: 81-92.
基金
国家重点研发计划（2016YFC0800200）; 国家自然科学基金（51779221）; 浙江省重点研发计划（2018C03031）; 浙江省“钱江人才”计划（QJD1602028）
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