Article
Engineering, Mechanical
Dattatraya G. Subhedar, Bharat M. Ramani, Kamlesh Chauhan, Hitesh Panchal, Sagar M. Prajapati, Ali Jawad Al-rubaie, Mustafa Musa Jaber
Summary: This study focuses on the effect of nanocoolant size on the radiator, with the aim of improving engine performance. The results show that using 0.2% Al2O3 nanoparticles in the coolant increases the overall heat transfer coefficient by 43% compared to the base fluid. Furthermore, a 65% reduction in frontal radiator area is possible with a 0.6% volume fraction nanocoolant, leading to decreased drag force and pumping power.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2023)
Article
Engineering, Ocean
Tiao-Jian Xu, Guo-Hai Dong, Ming-Fu Tang, Jun Liu, Wei-Jun Guo
Summary: This study conducted experiments on different types of net panels in extreme waves to analyze the hydrodynamic force, finding that the force heavily depended on the net solidity and KC number, and slightly on the net material. By establishing a wave force model, the study successfully predicted the forces on net panels in extreme waves, demonstrating that the model could simulate the loading process of the submerged net panels effectively.
APPLIED OCEAN RESEARCH
(2021)
Article
Mechanics
Shaohua Du, Yuxuan Zhao, Li Zhao, Qiang Zhou, Xiao Chen
Summary: In this study, particle-resolved direct numerical simulations were conducted to investigate the combined effects of Stefan Reynolds number, particle Reynolds number, separation distance, and relative orientation on the drag force exerted on particles in fluidized bed reactors. The results show that the blocking effect on inert particles in a tandem arrangement is weakened/strengthened with negative/positive Stefan flow due to the difference between the effective diameter and the real diameter of reactive particles. The drag force on the reactive particle decreases as Stefan Reynolds number increases, but the rate of reduction decreases as particle Reynolds number increases. The positive Stefan flow induces repulsion between the particles, leading to an increase in drag force on the inert particle. The Stefan flow has a negligible effect on the drag force of the inert particle when the separation distance is 3 times the particle diameter.
Article
Environmental Sciences
Su A. Kalloe, Bas Hofland, Jose A. A. Antolinez, Bregje K. van Wesenbeeck
Summary: In recent years, there has been considerable research on the capacity of vegetation to reduce wave impact. This study compares different methods to quantify the projected frontal-surface area (A(v)), and investigates their impact on wave attenuation. The findings suggest that terrestrial laser scans (TLS) underestimate A(v) and recommend applying a correction factor. Furthermore, the study demonstrates large differences in wave attenuation depending on the method used, highlighting the importance of selecting the appropriate method for accurate frontal-surface area estimations and reliable wave attenuation predictions.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Engineering, Biomedical
Elijah N. Holland, Deborah Lobaccaro, Jianping Fu, Andres J. Garcia
Summary: Cells integrate mechanical forces to sense and respond to signals, and cellular traction forces regulate cellular functions and tissue development. mPADs are a powerful tool for measuring traction forces, and this study investigated how mPAD top surface area affects cell spread area and traction forces. It was found that reducing the mPAD top surface area decreased cell spread area and traction forces, but the linear relationship between traction force and cell area remained, indicating cell contractility. The top surface area of mPADs is an important parameter to consider when measuring cellular traction forces, and the slope of the linear relationship provides a useful metric to characterize cell contractility.
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
(2023)
Article
Engineering, Marine
Yanxu Wang, Zegao Yin, Yong Liu
Summary: Coastal vegetation such as mangrove forests play a crucial role in coastal protection, and the parameterization of the drag coefficient is significant for characterizing the wave attenuation induced by vegetation. This study conducted physical experiments to investigate the hydrodynamics of mangrove and cylindrical models under wave conditions, and discussed the relationships between the local drag coefficients and the Reynolds number and Keulegan-Carpenter number.
Article
Environmental Sciences
D. Vettori, S. Niewerth, J. Aberle, S. P. Rice
Summary: The study found that different plant handling/storage procedures can significantly impact plant hydrodynamics even within a short period, with an approximately 30% variation in the mean drag coefficient across groups, comparable to variations found in different species of freshwater macrophytes in previous studies. Plants with the highest stress levels also exhibited the lowest drag coefficient among the groups considered, suggesting a potential link between plant stress and hydrodynamics.
WATER RESOURCES RESEARCH
(2021)
Article
Engineering, Chemical
Hamid Rezaei, C. Jim Lim, Shahab Sokhansanj
Summary: Wood pellet manufacturing involves drying wet biomass to a suitable moisture content; rotary drum dryers are the main drying equipment; misjudging particle residence time may lead to poor quality products and fires.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Mechanics
Akhil Marayikkottu Vijayan, Deborah A. Levin
Summary: This paper develops a multiphase gas-particle solver using the multiphase particle-in-cell (MP-PIC) approach to study the particle lifting mechanism in particle-laden electrostatic discharges. The solver is used to simulate the interaction of a shock wave with particles and investigate the forces affecting particle lifting. The study finds that quasi-steady drag, pressure gradient, added-mass, Saffman lift, and Magnus forces play important roles in particle lifting.
Article
Engineering, Civil
Casper C. A. Bekkers, Nikolas Angelou, Ebba Dellwik
Summary: Trees are crucial wind engineering elements in urban and agricultural settings. However, the understanding of their aerodynamics has been mainly focused on young and flexible trees. In this study, a new formulation of the classical drag equation is proposed to describe the aerodynamics of mature and wind-adapted trees. A full-scale experiment on an oak tree is conducted to determine the drag equation terms, and a novel photographic method is developed to accurately measure the frontal area of the tree. The results demonstrate the high efficiency of mature trees in reducing wind momentum, which can be useful in wind simulations and other tree measurement campaigns.
JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS
(2022)
Article
Engineering, Civil
Xiaoxia Zhang, Pengzhi Lin, Heidi Nepf
Summary: Marsh plants protect coasts and communities by dissipating wave energy through geometric and mechanical properties such as reconfiguration and mutual sheltering. This study developed a physically-based wave-damping model that incorporates the impact of leaves, reconfiguration, and sheltering. The model was validated and used to explore the effects of various wave and plant parameters on wave decay.
COASTAL ENGINEERING
(2022)
Article
Thermodynamics
Takashi Hibiki, Somboon Rassame
Summary: This study aimed to develop a simple and robust model for predicting the local interfacial area concentration (IAC) under steady-state bubbly flows with and without phase change. The model derived the dependent two-phase flow parameters of the IAC by considering bubble coalescence and breakup rates, and used a simplified turbulence model for computing the energy dissipation rate per unit mass. The prediction accuracy of the model was estimated to be 20% for adiabatic air-water bubbly flows and 40% for subcooled boiling flows with area-average void fraction values less than 10%.
APPLIED THERMAL ENGINEERING
(2023)
Article
Geosciences, Multidisciplinary
Hocheol Seo, Yeonjoo Kim
Summary: Wildfires have significant impacts on ecosystems and carbon-water fluxes on Earth. However, the representation of fire processes in land surface models is limited, especially in estimating burned areas in high northern latitudes. This study uses satellite data and model simulations to show that accurately simulating fires improves the estimation of carbon emissions and water fluxes in Alaska and Eastern Siberia. The study also finds that carbon emissions are more sensitive to wildfires in Alaska compared to Eastern Siberia, possibly due to differences in vegetation distribution. Additionally, water fluxes in Eastern Siberia are relatively insensitive to the size of the burned area due to the interaction between leaf area and soil moisture. This research improves our understanding of the role of burned areas in ecohydrological processes at high latitudes and highlights the need for improved approaches in predicting future carbon fluxes and climate change.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2023)
Article
Chemistry, Analytical
Jose M. Gonzalez-Rave, Francisco Moya-Fernandez, Francisco Hermosilla-Perona, Fernando J. Castillo-Garcia
Summary: This study aims to determine the frontal and lateral area of swimmers using an automated vision system and proposes a novel algorithm for estimation. The results provide important insights into the active drag in swimming and allow for better monitoring of swimmers during training sessions.
Article
Acoustics
Xia Liu, Tengfei Zheng, Chaohui Wang
Summary: In this study, a 3D model is presented to investigate the application of surface acoustic wave (SAW) technology in manipulating micro-nano particles. The distribution of acoustic pressure and acoustic streaming in a microchannel is studied using the improved limiting velocity method (ILVM). The motion of micro-particles of different diameters under the interaction of acoustic radiation force and drag force is simulated, showing that particles can move in three dimensions. These findings and methods are crucial for designing SAW microfluidic chips and precisely controlling particle motion.
Article
Marine & Freshwater Biology
Nikola Lenzewski, Kai Jensen, Kristin Ludewig
Summary: The study found that urban stormwater ponds have the potential for re-colonisation from seed bank, indicating that sowing is not necessary during the reconstruction process.
Article
Environmental Sciences
Celine E. J. van Bijsterveldt, Bregje K. van Wesenbeeck, Sri Ramadhani, Olivier Raven, Fleur E. van Gool, Rudhi Pribadi, Tjeerd J. Bouma
Summary: Although mangrove forests are relatively resilient to partial burial by plastic waste, our study shows that the abundance of plastic litter in mangroves can have negative impacts on vegetation growth and tree survival. Trees with 50% plastic cover exhibited surprising resilience, but trees with 100% plastic cover showed significantly decreased leaf area index and survival rates. This highlights the importance of addressing plastic pollution in mangrove ecosystems to prevent further deterioration of mangrove stands.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Civil
Timothy I. Marjoribanks, Maike Paul
Summary: Aquatic vegetation is crucial in coastal and riverine environments, with its geometric and biophysical properties affecting eco-hydraulic interactions. Variability in stem properties, such as rigidity, should be considered in modeling to accurately predict drag force. Failure to account for the reconfiguration of variable rigidity stems may lead to significant errors in predictions.
JOURNAL OF HYDRAULIC RESEARCH
(2022)
Article
Ecology
Linjing Ren, Kai Jensen, Philipp Porada, Peter Mueller
Summary: Research has shown that biotic interactions play a crucial role in regulating carbon cycling, particularly in blue carbon ecosystems. These interactions between plants, animals, and microbiota have strong effects on carbon fluxes across different spatial scales. Climate change-sensitive abiotic factors also influence the strength of biotic interactions on carbon cycling.
Article
Environmental Sciences
Dirk Granse, Mariana Romeiro Motta, Sigrid Suchrow, Klaus von Schwartzenberg, Arp Schnittger, Kai Jensen
Summary: Whole genome duplications lead to the formation of polyploid specimens in plants, which are considered as major drivers for speciation and diversification. In a study conducted in European Wadden Sea salt marshes, differences in distribution, phenotypic appearance, and response to surface elevation were identified between a hexaploid F-1-hybrid and its dodecaploid descendent, suggesting potential effects of ancient polyploidization on the observed cytotypic differences.
ESTUARIES AND COASTS
(2022)
Article
Environmental Sciences
Dirk Granse, Juergen Titschack, Malika Ainouche, Kai Jensen, Ketil Koop-Jakobsen
Summary: The study investigated the root system structures of polyploid Spartina taxa and found that the root-aerenchyma can facilitate oxygen transport, showing clear responses to habitat conditions based on different ploidy levels.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Forestry
Anastasia Leonova, Adrian Heger, Lizeth K. Vasconez Navas, Kai Jensen, Christoph Reisdorff
Summary: This study found that young trees had significantly higher fine root mortality during the summer drought in 2018, leading to low reforestation success in floodplains. The response of fine root dynamics differed between oak and elm trees, which may be attributed to differences in root distribution and hydraulic redistribution ability.
TREES-STRUCTURE AND FUNCTION
(2022)
Article
Environmental Sciences
Chris E. Blenkinsopp, Tom E. Baldock, Paul M. Bayle, Ollie Foss, Luis P. Almeida, Stefan Schimmels
Summary: The development of coastal regions and rising sea levels have increased the risk of coastal flooding. Traditional methods for measuring wave overtopping are not suitable for dynamically stable coastal protection structures. This study explores the potential use of 2D laser scanners to remotely sense the flow volumes overtopping a porous dynamic revetment and proposes two analysis methods to estimate the overtopping volumes.
Article
Engineering, Civil
C. E. Blenkinsopp, P. M. Bayle, K. Martins, O. W. Foss, L-P Almeida, G. M. Kaminsky, S. Schimmels, H. Matsumoto
Summary: The effects of climate change, sea level rise, and overpopulation are causing increasing stress on coastal regions. This paper presents a new methodology for predicting wave runup on composite beaches and dynamic cobble berm revetments, based on high-resolution measurements and insights from field and laboratory experiments.
COASTAL ENGINEERING
(2022)
Article
Marine & Freshwater Biology
Julia Bass, Dirk Granse, Ingo Hache, Kai Jensen, Volker Karius, Vanessa Minden, Martin Stock, Sigrid Suchrow, Michael Kleyer
Summary: The current climate crisis is leading to sea level rise, which poses a threat to coastal ecosystems. Salt marshes can only persist if their vertical accretion exceeds the rate of sea level rise. Plant functional traits, particularly leaf traits, have an impact on vertical accretion in salt marshes.
ESTUARINE COASTAL AND SHELF SCIENCE
(2022)
Article
Environmental Sciences
Svenja Reents, Iris Moeller, Ben R. Evans, Ken Schoutens, Kai Jensen, Maike Paul, Tjeerd J. Bouma, Stijn Temmerman, Jennifer Lustig, Matthias Kudella, Stefanie Nolte
Summary: Coastal protection provided by tidal wetland vegetation is crucial in defending coastlines against storm surges. This study examines how extreme wave events affect salt-marsh vegetation and whether plant properties influence plant resistance. The results reveal that salt-marsh vegetation is more robust than expected, with pioneer species showing higher resistance. The height of the vegetation canopy and the stiffness of stems also play a role in defining plant resistance.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Limnology
Eva Julia Marie Ostertag, Kai Jensen, Viktoria Unger, Stefanie Nolte
Summary: This study investigates the effects of active soil and passive air warming on seedling emergence and survival in salt marshes. The results show that warming has a significant influence on Shannon diversity, but no significant effects on seedling number and survival. However, there are trends that differ between zones, with seedling numbers slightly higher in the warming treatments in the pioneer zone and decreased in the high marsh. Median survival also differs significantly between species.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Multidisciplinary Sciences
Heather Alyson Shupe, Kai Jensen, Kristin Ludewig
Summary: Destructively sampling old Pedunculate oak trees to estimate carbon stocks and sequestration rates would harm the preservation of vulnerable floodplain forests. Instead, a nondestructive method using a 1-parameter equation based on diameter at breast height has been adapted to estimate carbon stocks and annual changes in carbon stock for individual trees, including above and below-ground carbon stocks. Additionally, there is a strong linear relationship between carbon sequestration rate and basal area increment.
Article
Forestry
Heather Alyson Shupe, Kai Jensen, Jens Oldeland, Kristin Ludewig
Summary: Trees can help reduce atmospheric CO2 concentrations, but the rate at which they do so varies. This study examines the carbon sequestration rate of Pedunculate oak trees in different floodplain environments and analyzes the effects of extreme events on this rate. The results show that floodplains are suitable areas for reforestation because dominant trees in these areas have a high carbon sequestration rate, even under severe conditions.
TREES FORESTS AND PEOPLE
(2022)
Article
Geosciences, Multidisciplinary
Suman Halder, Susanne K. M. Arens, Kai Jensen, Tais W. Dahl, Philipp Porada
Summary: Lycopsids, a distinct lineage of vascular plants, have evolved from tiny herbaceous plants to forest-like structures, enriching soil carbon pool and promoting soil microbial activity. They affect soil CO2, hydrology, and silicate weathering. A model, LYCOm, was developed to estimate the impacts of lycopsids on carbon uptake, weathering rates, and net primary production, highlighting their importance at the local scale. The study establishes a basis for assessing the biotic enhancement of weathering by lycopsids at the global scale and geological past, providing a novel approach for estimating their impacts on biogeochemistry and climate.
GEOSCIENTIFIC MODEL DEVELOPMENT
(2022)
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)
