Article
Environmental Sciences
Kyong Oh Baek, Dong Yeol Lee
Summary: This study develops a simple and practical formula for estimating transverse dispersion coefficients in meandering natural rivers, which are crucial for predicting solute transport. The formula relies on one dimensionless hydraulic parameter and is validated by comparing it with previously established equations. It is applied to natural river bends in the Nakdong River of Korea, showing promising accuracy. This formula offers a simplified approach to estimating transverse dispersion in meandering rivers when tracer and secondary flow data are unavailable, and can be further refined to capture the complex interplay between topography and transverse dispersion.
Rating: 8/1
Article
Environmental Sciences
Jiao Zhang, Wen Wang, Zhanbin Li, Huilin Wang, Qingjing Wang, Zhangyi Mi
Summary: This paper presents a random displacement model (RDM) to study material transport in emergent vegetated flow in natural rivers. By predicting the longitudinal dispersion coefficient, the RDM plays an important role in understanding the longitudinal transport of pollutants in rivers covered by emergent vegetation. The model is validated using experimental data and shows reliable estimates of the longitudinal dispersion coefficient.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Multidisciplinary Sciences
Xuewei Chu, Hanghang Ding, Xuemei Zhang
Summary: This study used laboratory experiments to simulate solute transport in the karst fissure-conduit aquifer system, revealing the influence of aquifer structures and tracer injection points on breakthrough curve shape. Results showed that different factors affect solute transport behaviors in the saturated karst aquifer system.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Electrical & Electronic
Nika Mlinaric, Natan Osterman
Summary: A new type of microfluidic flow sensor was proposed in this study, where velocity measurements are conducted on a second immiscible fluid in contact with the fluid sample. Observations and analysis of particle movement in side-cavities showed a linear correlation between their characteristic parameters and flow velocity in the main channel.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Mechanical
David L. Young, Ann Larsson, Donald R. Webster
Summary: This study presents simultaneous PIV and LIF measurements of a phase-locked meandering chemical plume, revealing asymmetric concentration fields and transverse profiles that can be modeled as Gaussian shapes. The research also indicates that large-scale alternating-sign vortices induced by the diverting plate are the dominant feature of the flow, influencing the meandering of the plume and the spatial distribution of concentration.
EXPERIMENTS IN FLUIDS
(2021)
Article
Engineering, Aerospace
Ziwan Li, Yixiang Yuan, V. L. Varsegov, Baoting Guo, Bo Xiao, P. H. Duan
Summary: This paper studies the mixing characteristics of circular transverse gas fuel jet in crossflow, showing that a well-mixed mixture is formed in the recirculation zone with high combustion efficiency.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Ecology
S. A. Hashemi Monfared, C. L. Walsh, T. P. Curtis, A. P. Jarvis, M. Dehghani Darmian, F. Khodabandeh
Summary: The accuracy of water quality predictions is crucial, especially in countries impacted by climate change and ecological water diversity. Water quality modeling in rivers is a valuable tool for decision-making in surface water management due to the limitations of sampling methods. This research focuses on the effects of river geometry and meandering on pollutant transport process.
ECOLOGICAL INFORMATICS
(2023)
Article
Engineering, Mechanical
David L. Young, Donald R. Webster, Ann Larsson
Summary: This study investigates the turbulent mixing in a meandering non-buoyant chemical plume using high-resolution measurements of velocity and concentration fluctuations. The results show that the spatial distribution of turbulent quantities is influenced by large-scale alternating-sign vortices. The spatial variation of turbulent flux agrees well with the phase-averaged concentration gradient, and the eddy diffusivity framework effectively models the turbulent flux.
EXPERIMENTS IN FLUIDS
(2022)
Article
Environmental Sciences
Jaehyun Shin, Il Won Seo
Summary: This research developed a two-dimensional shallow water model to analyze the shear effect of secondary currents in a meandering channel. A new equation for the vertical velocity profile with nonlinear shear effects was derived from the equation of motion. Incorporating the ratio of depth to radius-of-curvature into the shear intensity of the secondary flow improved the accuracy of simulating primary velocity distributions in meandering channels.
Article
Environmental Sciences
Daniel R. Lester, Marco Dentz, Prajwal Singh, Aditya Bandopadhyay
Summary: This study compares the transverse macrodispersion in porous media with different conductivity structures under purely advective transport. It is found that porous media with smooth, locally isotropic hydraulic conductivity exhibit zero transverse macrodispersion, while non-smooth or locally anisotropic conductivity fields can generate transverse macrodispersion. These findings provide insights into the mechanisms that govern transverse macrodispersion in groundwater flow.
WATER RESOURCES RESEARCH
(2023)
Article
Thermodynamics
Ziwan Li, Yixiang Yuan, Jun Yao, V. L. Varsegov, P. H. Duan, Lu Zhao
Summary: This paper investigates a new method of using circular transverse jet to improve combustion efficiency at off-design conditions. Results show that this method can effectively mix fuel and mainstream airflow, leading to combustion efficiency reaching over 99% under specific conditions. The study of flow field structure and temperature distribution in the combustion zone lays the foundation for further research and engineering application.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Multidisciplinary Sciences
Vishal Panwar, Cassandra N. Vargas, Cari S. Dutcher
Summary: The study explores the mixing dynamics of complex oil-in-water emulsions by using Taylor-Couette flow with radial fluid injection. By measuring changes in reflected light intensity and droplet size distribution, the impact of flow field and mixing conditions on emulsion stability is investigated. The results demonstrate the tunable nature of the final droplet size distribution based on salt concentration, observation time, and mixing flow state in the Taylor-Couette cell.
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2023)
Article
Environmental Sciences
Merenchi Galappaththige Nipuni Odara, Jonathan Pearson
Summary: This study presents a methodology for deriving the coefficient of longitudinal dispersion in the presence of submerged vegetation based on velocity measurements and a mixing length approach. Experimental results show that the longitudinal dispersion is influenced by the height and properties of the submerged vegetation.
Article
Engineering, Civil
Lauren E. E. Schwab, Chris R. R. Rehmann
Summary: An expression for the transverse mixing coefficient in a rectangular channel is derived to evaluate the importance of transverse turbulent diffusion. Both vertical and transverse turbulent diffusion contribute appreciably to transverse shear dispersion, and the direct contribution of transverse turbulent diffusion to transverse mixing is important for a range of conditions commonly observed in natural channels. A comparison of predicted and measured transverse mixing coefficients supports including turbulent diffusion in analyses of transverse mixing - both in its effect on shear dispersion and as a direct mechanism of transport.
JOURNAL OF HYDRAULIC RESEARCH
(2023)
Article
Thermodynamics
Zhiyong Shu, Wenqing Liang, Xiaohong Zheng, Gang Lei, Peng Cao, Wenxiao Dai, Hua Qian
Summary: A simplified prediction model was proposed to predict hydrogen dispersion and validated by experiments using helium. The model accurately predicts concentration at the central axis under certain conditions. Factors affecting dispersion were explored in the experiments, and results showed accurate predictions in specific scenarios.
