Article
Mechanics
G. C. Yang, Y. J. Huang, Y. Lu, C. Y. Kwok, Y. D. Sobral, Q. H. Yao
Summary: This research treats granular materials as a continuum and uses the lattice Boltzmann method to simulate their flow behavior. A novel frictional boundary condition is introduced to accurately describe the stick-slip phenomenon at the boundaries. The numerical model shows good agreement with analytical solutions and can predict various granular flow scenarios.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Remi Chassagne, Cyrille Bonamy, Julien Chauchat
Summary: This research investigates the modelling of collisional bedload transport, with a particular focus on the continuum modelling of granular flow. A frictional-collisional approach that combines a Coulomb model with the kinetic theory of granular flows is developed. By comparing with coupled fluid-discrete simulations, it is found that the classical kinetic theory model fails to accurately reproduce the simulations, which can be attributed to the neglect of interparticle friction and the absence of a saltation model in the continuum approach. Modifications that take into account interparticle friction and a saltation model are proposed and the resulting model successfully reproduces the mu(I) rheology in the dense regime of granular flow. Experimental evaluation shows significant improvements in granular flow modelling.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Jiarui Li, Kun Xue, Junsheng Zeng, Baolin Tian, Xiaohu Guo
Summary: This paper investigates the shock-induced instability of interfaces between gases and dense granular media with finite length using a computational fluid dynamics method. The shock-driven granular instability is found to be governed by different mechanisms from the Richtmyer-Meshkov instability, resulting in a growth law distinct from the latter. The study also establishes instability criteria for granular media with different lengths, showing a scaling growth law that collapses data from varying cases.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Cheng-Hsien Lee
Summary: This study developed a multiphase model with a novel evolution equation to address the issues of shear-induced volume change and pore-pressure feedback in submarine granular flows simulated using an Eulerian-Eulerian two-phase model. The evolution equation effectively describes the relaxation process of static solid pressure and shear-induced volume change, allowing the model to capture phenomena such as time delays in initiating flows and different collapse processes for differently packed columns.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Physics, Multidisciplinary
D. R. Russell, G. C. Burdiak, J. J. Carroll-Nellenback, J. W. D. Halliday, J. D. Hare, S. Merlini, L. G. Suttle, V. Valenzuela-Villaseca, S. J. Eardley, J. A. Fullalove, G. C. Rowland, R. A. Smith, A. Frank, P. Hartigan, A. L. Velikovich, J. P. Chittenden, S. V. Lebedev
Summary: This study presents the investigation of perpendicular subcritical shocks in a collisional laboratory plasma. The shocks are generated by placing obstacles in the supermagnetosonic outflow from an inverse wire array z pinch. The existence of subcritical shocks in this regime is demonstrated, and it is found that secondary shocks form in the downstream. Detailed measurements confirm the absence of a hydrodynamic jump in the subcritical shock structure. The calculated resistive diffusion length is approximately equal to the shock width. Little heating is observed across the shock, indicating a lack of viscous dissipation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Engineering, Chemical
Jianbo Fei, Zhihao Liu, Muhammad Irslan Khalid, Yuxin Jie, Xiangsheng Chen
Summary: This study develops a dynamic model to describe the frictional-dilatancy behavior of underwater granular motion and verifies the accuracy of the model.
Article
Physics, Applied
Eleftherios Ioannou, Nikolaos Nikiforakis
Summary: Detonators are explosive devices used for initiating secondary explosives, with their initiating capability being a critical factor for safe and effective use. This study employs numerical simulations to investigate the blast wave generated by detonators and examines their initiating capability, revealing that differences in blast wave characteristics between detonators in the near field do not persist in the far field.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Mechanics
Kun Xue, Lvlan Miu, Jiarui Li, Chunhua Bai, Baolin Tian
Summary: The explosive dispersal of granular media is challenging to control or characterize due to the complex particle-flow coupling. In this study, the central explosion-driven dispersal of dense particle layers is investigated using computational fluid dynamics-discrete element method. Different dispersal modes are categorized and corresponding thresholds are proposed based on characterizing parameters. Continuum models are also developed to identify ideal dispersal modes and provide insights into the origins of particle-scale patterns.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Laurent Lacaze, Joris Bouteloup, Benjamin Fry, Edouard Izard
Summary: This study investigates the collapse of a granular column in a liquid using numerical simulations, focusing on the influence of Stokes number St and the initial volume fraction phi(i) on the dynamics of the collapse. A dedicated numerical model with a discrete element method is used to provide a comprehensive description of the granular phase in dense granular flows. The research aims to characterize the dynamics of the collapse and its final deposit in relation to (St, phi(i)), as well as to describe the granular rheology and dilatancy effects based on these two dimensionless numbers.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Jiahui Hao, Yanjie Li, Yi Liu, Jennifer S. Curtis, Yu Guo
Summary: This study examines the jamming phenomenon in shear flows of cylindrical particles with different size distributions and found that at the jamming volume fraction, stress fluctuation and granular temperature reach their maximum values, while the alignment degree of cylindrical particles reaches a minimum.
ADVANCED POWDER TECHNOLOGY
(2021)
Article
Physics, Fluids & Plasmas
G. C. Yang, L. Jing, C. Y. Kwok, Y. D. Sobral
Summary: The study found that larger underwater granular collapses result in higher flow mobility and longer runout distances. This is due to the larger column size transferring more potential energy into kinetic energies of the fluid and particles, leading to a more efficient energy conversion and higher mobility in larger cases.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Geosciences, Multidisciplinary
Alexander M. Taylor-Noonan, Elisabeth T. Bowman, Brian W. McArdell, Roland Kaitna, Jim N. McElwaine, W. Andy Take
Summary: The presence of a pore fluid significantly increases the mobility of granular flows. Wet granular flows show flow dilation and strong variation in velocity profile, resulting in higher mobility compared to dry flows. Experimental results also reveal the influence of source volume on flow behavior.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Mechanics
Lise Ceresiat, Jari Kolehmainen, Ali Ozel
Summary: The study derives the charge transport equation for bidisperse granular flows with contact electrification, and evaluates the revisited hydrodynamic equations and derived charge transport equation through hard-sphere simulations.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Ronald A. Remmerswaal, Arthur E. P. Veldman
Summary: The interface curvature is crucial for the modelling of surface tension in capillary driven flow. Traditional geometric volume of fluid (VOF) methods based on a piecewise linear interface approximation fail to converge under mesh refinement in time-dependent problems. Instead, the proposed piecewise parabolic interface calculation (PPIC) methods, specifically the parabolic LVIRA and MOF methods (PLVIRA and PMOF), accurately capture the interface dynamics. Numerical experiments demonstrate improved reconstruction accuracy, convergence of interface curvature, and Weber number independent convergence in droplet translation problems when using the PPIC methods coupled with a two-phase Navier-Stokes solver. The PLVIRA method is successfully applied to the simulation of a 2D rising bubble, showing good agreement with a reference solution.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Mechanics
Vicente Garzo
Summary: Understanding the transport of particles in a carrier fluid is a challenging task. The proposed two-fluid model by Chassagne et al. takes into account interparticle friction and the saltation regime, providing a better understanding of the macroscopic properties of granular flows. The model agrees with simulations and experimental results, demonstrating its reliability.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Cell Biology
Xiao-Lin Shen, Jin-Feng Yuan, Xuan-He Qin, Guang-Ping Song, Huai-Bin Hu, Hai-Qing Tu, Zeng-Qing Song, Pei-Yao Li, Yu-Ling Xu, Sen Li, Xiao-Xiao Jian, Jia-Ning Li, Chun-Yu He, Xi-Ping Yu, Li-Yun Liang, Min Wu, Qiu-Ying Han, Kai Wang, Ai-Ling Li, Tao Zhou, Yu-Cheng Zhang, Na Wang, Hui-Yan Li
Summary: The study reveals the crucial role of the linear ubiquitin chain assembly complex in ciliogenesis and uncovers the direct mechanism of CP110 removal. This finding provides a new therapeutic target for cilia-associated diseases.
JOURNAL OF CELL BIOLOGY
(2022)
Article
Mechanics
Kang He, Huabin Shi, Xiping Yu
Summary: The effects of interstitial water on the collapse of partially immersed granular columns were investigated experimentally and numerically. It was found that the interstitial water generally speeds up the collapse of coarse-grain columns but slows down the motion of fine-particle columns. The particle-fluid two-phase model used in the study validated the experimental results and clarified the roles of drag force and pressure gradient force in the collapse of both coarse- and fine-grain columns.
Article
Engineering, Marine
Nguyen Xuan Tinh, Hitoshi Tanaka, Xiping Yu, Guangwei Liu
Summary: This study investigated the bottom boundary layer induced by tsunamis, based on the actual waveforms obtained during the 2011 Great East Japan Earthquake tsunami. The results showed that the thickness of the tsunami boundary layer is extremely thin compared to the water depth, and the velocity distribution is similar to that of the bottom boundary layer under wind-generated waves. The study also found that the flow regime transitions from smooth turbulence to rough turbulence, leading to a greater gradient of flow across the layer than in the steady flow direction.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Computer Science, Interdisciplinary Applications
Wei Pan, Stephan C. Kramer, Matthew D. Piggott, Xiping Yu
Summary: The new two-layer model developed based on discontinuous Galerkin finite element discretization simulates the generation of impulsive waves by deformable granular landslides, accurately describing the complex behaviors of granular landslides from initiation to deposition and the subsequent wave generation and propagation.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS
(2022)
Article
Environmental Sciences
Xindi Chen, Changkuan Zhang, Ian H. Townend, Zheng Gong, Qian Feng, Xiping Yu
Summary: This study investigates the effects of different depositional histories on sand-attached benthic biofilms in aquatic environments. The results show that biostabilization is disturbance-stimulated, contrary to previous beliefs. Intensively disturbed bio-sandy beds exhibit a more rapid increase in bed strength and stability. The findings have implications for the understanding of the role of biofilms as ecosystem engineers.
WATER RESOURCES RESEARCH
(2022)
Review
Mechanics
Yilong Liu, Xiping Yu
Summary: This paper reviews the research published in the past century on the drag force acting on an assemblage of particles moving relative to its carrier fluid. It summarizes representative results valid in each flow regime and verifies existing formulas for the drag coefficient while establishing a new one. The new formula is shown to be more accurate than others and converges to established laws and cases under different conditions.
Review
Pediatrics
Juanjuan Zhang, Jun'an Zeng, Liangjuan Zhang, Xiping Yu, Jinzhen Guo, Zhankui Li
Summary: Early stage diagnosis of neonatal sepsis is still a challenging issue, and the full blood count can serve as a cheap, universal, and rapid diagnostic test. This study found that the immature-to-total neutrophil ratio, immature-to-mature neutrophil ratio, and neutrophil-to-lymphocyte ratio can improve the accuracy of neonatal sepsis diagnosis. However, further studies are needed to validate these findings due to heterogeneity and limited research.
FRONTIERS IN PEDIATRICS
(2022)
Article
Mechanics
Xinglin Pan, Yan Zhou, Ping Dong, Huabin Shi
Summary: This paper develops an improved boundary scheme for meshless methods, addressing the issue of implementing impermeable solid boundary condition. The scheme satisfies the Pressure Poisson's Equation in the local integration domain and eliminates the need for artificial treatment. Experimental results demonstrate higher accuracy in pressure and velocity with this scheme.
EUROPEAN JOURNAL OF MECHANICS B-FLUIDS
(2022)
Article
Public, Environmental & Occupational Health
Xingyuan Zhou, Min Guo, Zhifei Li, Xiping Yu, Gang Huang, Zhen Li, Xiaohong Zhang, Liya Liu
Summary: This study investigated the relationship between hospitalization rates for pneumonia and asthma in children under 5 years old and the concentration of air pollutants in Ningbo. The results showed that PM2.5, PM10, SO2, and NO2 were significantly associated with hospitalization rates for pneumonia and asthma. For every 10-unit increase in lag03 air pollutant concentration, hospitalization rates increased by 2.22%, 1.94%, 11.21%, and 5.42% for PM2.5, PM10, SO2, and NO2, respectively. These findings highlight the urgent need to improve air quality and reduce pediatric hospitalizations due to respiratory illness.
FRONTIERS IN PUBLIC HEALTH
(2023)
Article
Mechanics
Xiafei Guan, Huabin Shi
Summary: The variation of momentum of deformable submarine landslides off a slope is investigated, and it is found that most of the landslide momentum is lost during further propagation. Scaling relations of the spatial-temporal maximum transport rate and flux of the landslide momentum are proposed, providing a practical method for estimating the run-out of real submarine landslides and their impact on underwater infrastructure.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Marine
Junliang Gao, Shukai Gong, Zhiwei He, Huabin Shi, Jun Zang, Tao Zou, Xu Bai
Summary: Fluid resonance can occur between two side-by-side vessels, leading to amplification of wave height and increased wave loads and motion responses of the vessels. This study uses the OpenFOAM software to simulate the steady-state resonance phenomenon between two side-by-side boxes under incident regular waves, with the upriver box fixed and the downriver box heaving freely. The study investigates the influence of the vertical degree of freedom of the downriver box and the relative position of the heaving box on the wave loads exerted on both boxes during the steady-state gap resonance.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Multidisciplinary Sciences
Kaiyue Shan, Yanluan Lin, Pao-Shin Chu, Xiping Yu, Fengfei Song
Summary: The research finds that there has been a significant seasonal advance of intense tropical cyclones (TCs) in most tropical oceans since the 1980s. This advance is closely related to the seasonal advance of rapid intensification events and is primarily driven by greenhouse gas forcing. The advance of intense TCs will increase the likelihood of intersecting with other extreme rainfall events, leading to disproportionate impacts.
Article
Engineering, Geological
Wenxin Li, Huabin Shi, Xiping Yu
Summary: In this paper, the effects of interstitial fluid on frictional behaviors of particle contacts were studied using an Euler-Lagrange model. The formulation of the friction coefficient for immersed particle contacts, taking into account the effects of interstitial fluid viscosity and pressure, was proposed based on laboratory experiments. The model was verified and validated through experiments and simulations, showing the importance of considering the effects of interstitial fluid and the enhancement effect of porosity in granular materials.
Article
Geosciences, Multidisciplinary
Yue Xu, Xiping Yu
Summary: Accurate description of wind energy input into ocean waves is crucial for wave modeling. This study evaluates the performance of an improved formula that considers the effect of wave breaking and airflow separation on steep wave crests. Coupling an enhanced atmospheric wave boundary layer model with the ocean wave model WAVEWATCH III, numerical results show that the improved model leads to more accurate results under all conditions, with better performance than other standard options. The improvement is particularly important for waves in their early development stage and in shallow waters.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Engineering, Civil
Kuifeng Zhao, Yufei Wang, Philip L. -F. Liu
Summary: This note provides guidelines for selecting appropriate analytical periodic water wave solutions based on two physical parameters. The guidelines are summarized in a graphic format and the dividing lines between applicable wave theories are determined by the nonlinearity and frequency dispersion ratios.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Jana Haddad, Johanna H. Rosman, Richard A. Luettich, Christine M. Voss
Summary: Understanding wave transformation in marsh vegetation canopies is crucial for assessing nature-based shoreline strategies. This study investigates the challenges of accurately modeling wave dissipation in coastal marshes and proposes a new dimensionless parameter to represent the canopy drag coefficient (C-D). The study finds that uncertainties in vegetation measurements lead to variations in C-D expressions, and suggests using the Cauchy number (Ca) as the more appropriate parameter for larger waves.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Dirk P. Rijnsdorp, Arnold van Rooijen, Ad Reniers, Marion Tissier, Floris de Wit, Marcel Zijlema
Summary: This paper extends the non-hydrostatic wave-flow model SWASH to account for the influence of a depth-uniform ambient current on wave dynamics. The model's ability is verified by comparing predictions to results from linear theory, laboratory experiments, and a spectral wave model. The extended model accurately captures current-induced changes in the wave field and simulations of wave dynamics in the presence of strong opposing currents.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Zhihao Shen, Duruo Huang, Gang Wang, Feng Jin
Summary: In this study, a resolved CFD-DEM coupling procedure was proposed to study the interaction of waves and irregularly shaped armour units. The model was validated by comparing the numerical results with a flume wave erosion test. The influence of armour shape on overtopping discharge, pressure distribution, and vortex structure was also studied.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Xinyu Hou, Zhonghua Weng, Xin Chen, Gengfa Chen
Summary: A single-phase model is proposed to predict sediment motion on vortex rippled bed under wave action. The model takes into account the acceleration effect of bottom sediment, the development of asymmetric boundary layer, and the sediment phase-lag, and successfully predicts the velocity, concentration, and development of sediment cloud on vortex ripples.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Mark Loveland, Eirik Valseth, Jessica Meixner, Clint Dawson
Summary: This article discusses the importance of using numerical models to predict the wind wave spectrum of the ocean. The article explores various finite element discretizations of the Wave Action Balance Equation and examines their convergence properties through simplified 2-D test cases. It also introduces a new spectral wind wave model called WAVEx and its implementation method.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Yuan Li, Chi Zhang, Shaohua Zhao, Hongshuai Qi, Feng Cai, Jinhai Zheng
Summary: Sandy-muddy transitional beaches (SMT-Beaches) are a type of coastal formation consisting of upper sandy beach and lower mudflat. This study examined the morphological characteristics of SMT-Beaches and the mechanisms of the formation of sandmud transition (SMT) boundary. Field surveys were conducted on SMT-Beaches in South China Coasts and a new equilibrium profile function for SMT-Beaches was developed. The function demonstrated good performance and improved accuracy compared to traditional methods. It was also found that sediment characteristics differ on both sides of the SMT boundary, with clay-to-silt grains increasing seaward.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
He Ma, Ludi Xu, Samuel Ukpong Okon, Peng Hu, Wei Li, Huabin Shi, Zhiguo He
Summary: This study presents a coupled model to predict morphodynamic changes during storm surges. The model accurately simulates the morphological evolution of the Santa Rosa barrier island caused by Hurricane Ivan's storm surge.
COASTAL ENGINEERING
(2024)
Article
Engineering, Civil
Myung Jin Koh, Hyoungsu Park, Albert S. Kim
Summary: A framework combining tsunami flow model and debris transport model is developed to evaluate the kinematics of multiple debris and sequential hazards in a coastal community. The impact of tsunami-driven debris at Honolulu Harbor, Hawaii is assessed by simulating the motion of 2500 shipping containers under a hypothetical tsunami event. New types of intensity measures for tsunami-driven debris hazards are introduced, and hazard maps showing the potential impact loadings from debris dispersion are presented.
COASTAL ENGINEERING
(2024)