Channel Velocity Research Articles

Analytical model for predicting the lateral profiles of velocities through a partially vegetated channel

In an open channel, an emergent canopy of vegetation enhances local resistance, producing a complicated velocity distribution within and around the canopy. Laboratory experiments were performed to understand the flow velocity variations in a partially vegetated channel, revealing both streamwise and lateral velocity variations as the flow entered the canopy. An analytical model was proposed to predict the lateral velocity profiles across the vegetated region and bare channel in both the flow adjustment region and the fully developed flow region. The flow velocity variations in the streamwise and lateral directions were parameterized and included in the new proposed model, allowing the model to capture both the streamwise and the lateral velocity variations. Twenty sets of experimental data from our experiments and data from published studies were used to verify the new model. The predicted velocity profiles exhibited good agreement with the measurements under a wide range of vegetation and flow conditions, suggesting that the proposed model is capable of accurately predicting the velocity profiles in a partially vegetated channel. Finally, the proposed model was applied to evaluate the critical frontal area per canopy volume at which Kelvin–Helmholtz vortices form along the emergent canopy side edge. With the same spatially averaged velocity, the critical frontal area exhibited no dependence on stem diameter.

Persistent red blood cells retain their ability to move in microcapillaries under high levels of oxidative stress

Oxidative stress is one of the key factors that leads to red blood cells (RBCs) aging, and impairs their biomechanics and oxygen delivery. It occurs during numerous pathological processes and causes anaemia, one of the most frequent side effects of cancer chemotherapy. Here, we used microfluidics to simulate the microcirculation of RBCs under oxidative stress induced by tert-Butyl hydroperoxide. Oxidative stress was expected to make RBCs more rigid, which would lead to decrease their transit velocity in microfluidic channels. However, single-cell tracking combined with cytological and AFM studies reveals cell heterogeneity, which increases with the level of oxidative stress. The data indicates that the built-in antioxidant defence system has a limit exceeding which haemoglobin oxidation, membrane, and cytoskeleton transformation occurs. It leads to cell swelling, increased stiffness and adhesion, resulting in a decrease in the transit velocity in microcapillaries. However, even at high levels of oxidative stress, there are persistent cells in the population with an undisturbed biophysical phenotype that retain the ability to move in microcapillaries. Developed microfluidic analysis can be used to determine RBCs’ antioxidant capacity for the minimization of anaemia during cancer chemotherapy.

Lithospheric Structure of the South India Precambrian Terrains From Surface Wave Tomography

AbstractWe have developed a 3‐D shear velocity (Vsv) model of Precambrian terrains of South India with a lateral resolution of 55 km to a depth of 250 km by inversion of fundamental mode Rayleigh wave phase velocity dispersion data in the period of 30–140s, combined with a well‐constrained crustal velocity model from an earlier study. The dispersion data were computed from 748 earthquakes recorded at 85 homogeneously distributed seismographs. Our velocity model shows 150–200 km thick lithosphere in most of the Archean Dharwar craton where Vsv is >4.7 km/s in the depth of 50–100 km and progressively decreases to 4.6 km/s at 120–150 km followed by a constant velocity of 4.5 km/s beyond 150–200 km depth. It correlates well with the results of the petrological studies of kimberlite xenoliths. An extraordinary high shear velocity (up to 4.8 km/s) and thick lithosphere (150 km) are observed beneath the Proterozoic Carbonatite complex, located at the south‐eastern edge of the Dharwar craton. We infer compositional modification of lower lithosphere at the south‐western margin of the Dharwar craton and lithospheric erosion at the Granulite terrain both possibly due to interaction with the Marion mantle plume at ∼90 Ma. The region is underlain by a 2%–3% lower velocity channel at ∼180–220 km depth in the asthenosphere, uncorrelated with the overlying lithosphere, possibly due to relative motion between them. It may be attributed to deep Earth‐processes such as asthenospheric upwelling.

Predicting Bulk Average Velocity with Rigid Vegetation in Open Channels Using Tree-Based Machine Learning: A Novel Approach Using Explainable Artificial Intelligence.

Predicting the bulk-average velocity (UB) in open channels with rigid vegetation is complicated due to the non-linear nature of the parameters. Despite their higher accuracy, existing regression models fail to highlight the feature importance or causality of the respective predictions. Therefore, we propose a method to predict UB and the friction factor in the surface layer (fS) using tree-based machine learning (ML) models (decision tree, extra tree, and XGBoost). Further, Shapley Additive exPlanation (SHAP) was used to interpret the ML predictions. The comparison emphasized that the XGBoost model is superior in predicting UB (R = 0.984) and fS (R = 0.92) relative to the existing regression models. SHAP revealed the underlying reasoning behind predictions, the dependence of predictions, and feature importance. Interestingly, SHAP adheres to what is generally observed in complex flow behavior, thus, improving trust in predictions.

The Galactic dynamics revealed by the filamentary structure in atomic hydrogen emission

We present a study of the filamentary structure in the neutral atomic hydrogen (H I) emission at the 21 cm wavelength toward the Galactic plane using the 16′.2-resolution observations in the H I 4π (HI4PI) survey. Using the Hessian matrix method across radial velocity channels, we identified the filamentary structures and quantified their orientations using circular statistics. We found that the regions of the Milky Way’s disk beyond 10 kpc and up to roughly 18 kpc from the Galactic center display H I filamentary structures predominantly parallel to the Galactic plane. For regions at lower Galactocentric radii, we found that the H I filaments are mostly perpendicular or do not have a preferred orientation with respect to the Galactic plane. We interpret these results as the imprint of supernova feedback in the inner Galaxy and Galactic rotation and shear in the outer Milky Way. We found that the H I filamentary structures follow the Galactic warp and flaring and that they highlight some of the variations interpreted as the effect of the gravitational interaction with satellite galaxies. In addition, the mean scale height of the filamentary structures is lower than that sampled by the bulk of the H I emission, thus indicating that the cold and warm atomic hydrogen phases have different scale heights in the outer galaxy. Finally, we found that the fraction of the column density in H I filaments is almost constant up to approximately 18 kpc from the Galactic center. This is possibly a result of the roughly constant ratio between the cold and warm atomic hydrogen phases inferred from the H I absorption studies. Our results indicate that the H I filamentary structures provide insight into the dynamical processes shaping the Galactic disk. Their orientations record how and where the stellar energy input, the Galactic fountain process, the cosmic ray diffusion, and the gas accretion have molded the diffuse interstellar medium in the Galactic plane.

Research of AQUILA molecular cloud on formaldehyde (H2CO) wave length based on radioastronomic observations

One of the most important tasks of astrophysics is to study areas and processes of star formation. Since the molecular clouds of the interstellar medium of the Galaxy are the most important structures in the regions of star formation, the study of their composition, internal structure, origin and evolution will make a significant contribution to solving this problem. A molecular cloud is a type of interstellar cloud whose density and size allow molecules and various complex compounds to form in it. Because of their complex structure, molecules have a lot of spectral lines in the radio range. In this regard, in this study, we studied the data of radio astronomy observations at the wavelength of a formaldehyde molecule (H2CO). The aim of this study is to search for star formation regions in the early stages of evolution by studying the Aquila molecular cloud at the wavelength of a formaldehyde molecule (H2CO). This study presents the results of the first radio astronomical observations of the H2CO formaldehyde molecule in the southern regions of W40 and Serpens South of the Aquila molecular cloud, obtained during February 2015 at the 26m Nanshan radio telescope of the Xinjiang Astronomical Observatory of the Chinese Academy of Sciences. Data were obtained on the absorption line of formaldehyde H2CO (l10-l11)  (λ=6 см, ν0 = 4829.6594 МHz). The study also used archival data obtained by observing 12СО(2−1) and 13CO(2−1) and 6 cm continuum molecules for the Aquila Rift region. Maps of the integral absorption intensity of H2CO, maps of the distribution of the centroid rate of absorption of H2CO and 13CO radiation (1−0), distributions of the 6 cm radio continuum superimposed on integrated H2CO absorption contours, a map of the H2CO line width, the distribution of the excitation temperature   of the H2CO absorption lines, and H2CO channel velocity to the Aquila molecular cloud. The H2CO excitation  was determined by which a new star formation region was detected in the Serpens 3 region.

Precise prediction of the collapse column based on channel wave spectral disparity characteristics and velocity tomography imaging

Abstract Collapse columns are complex geological anomalies that present safety hazards in coal mines. In practice, the boundaries and internal features are difficult to finely characterize. In this study, we use the Jeffrey divergence to reveal the spectral disparity when the channel wave seismic ray path encounters a collapse column. We use the forward mode and applications for verification. We find that the centroid peak frequency shifts toward lower frequencies, the frequency band narrows and the rays through a collapse column cause attenuation of energy. When a seismic ray path encounters a large collapse column, no channel wave appears in the seismic record, the dispersion curve velocity is greater than the velocity of a normal coal seam, the centroid peak frequency drops and the frequency band shrinks. When a seismic ray passes through the boundary of a collapse column, the dispersion curve shows two parallel velocity phases. When a seismic ray path passes through a small collapse column, the decrease in the centroid frequency becomes the only identifying feature. The proposed channel wave spectral disparity characteristic and velocity tomography imaging method can effectively identify small collapse columns and improve the accuracy and precision of the location of collapse column boundaries, with a position deviation of less than 10 m.

Investigation of hydrogen-air and acetylene-air flame propagation through porous media using infrared visualisation

One of the modern energy safety concerns is ensuring explosion safety when working with flammable gases. For this purpose, various methods are used, such as active chemical inhibitors and passive combustion suppression. The use of various porous materials is prevalent among passive methods for combustion suppression. This study focused on the experimental investigation of hydrogen-air and acetylene-air flame propagation through polyurethane foam and through the empty channel. The use of high-speed infrared camera enabled visualization of flame propagation inside the porous material. Two types of diagnostic channels were used with the dimensions of the diagnostic section 16 × 20 mm and 40 × 20 mm. The length of the foam was 120 mm. In hydrogen-air mixtures with 10 pores per inch (PPI) polyurethane foam the flame velocity was higher than in the empty section; with 30 PPI polyurethane foam the flame was quenched in the mixture with equivalence ratio ER = 0.3, but for mixtures with ER = 0.4 and ER = 0.5 the average flame velocity was higher than in the empty channel. In the acetylene-air mixtures flame velocity was usually lower in polyurethane foam and only reached the flame velocity in the empty channel with ER = 0.8 and 10 PPI foam. Critical Peclet numbers that allowed the flame to propagate through porous materials were calculated based on the obtained experimental data. The critical Peclet numbers were 23–24 for the hydrogen-air mixture and 37–38 for the acetylene-air mixture. The channel was open near the ignition point, which allowed the obtained results to be less dependent on the channel length. Information obtained in this work can be used to improve the means of ensuring explosion safety, including in the areas of nuclear power and transport using hydrogen.

Numerical Simulation of Turbulent Flow in Bends and Confluences Considering Free Surface Changes Using the Volume of Fluid Method

The impact of secondary flows on the flow velocity in open channel bends and confluences was simulated using three-dimensional (3D) numerical models. The Reynolds-averaged Navier–Stokes equation system was utilized as the governing equations and two different turbulence models were employed in this study: the standard k-ε model and the realizable k–ε model. In a recent study by the authors, the rigid lid approach was used, which does not allow for vertical displacement of the water surface. In this study, the simulation of free surface displacements was simulated using the volume of fluid free-surface tracking method. The numerical models were evaluated and validated by using the experimental data of a sharply curved channel and a confluent channel. The accuracies of the two turbulence models were evaluated and discussed. This study found that both models can satisfactorily reproduce the experimental data. However, the standard k–ε model performed better for the curved channel case while the Realizable k–ε model performed better for the confluent channel case.

Simultaneous measurement of the structures of the velocity and thermal boundary layers in the rod bundle channel

The complex geometry of the rod bundle fuel assemblies makes the measurement of velocity and temperature difficult, which hinders the design and optimization of the thermohydraulic performance of the advanced fuel assemblies. In the present study, Particle Image Velocimetry (PIV) and Laser-Induced Fluorescence (LIF) techniques are used to simultaneously measure and reconstruct the structures of the velocity and thermal boundary layers. The velocity and temperature distributions near the rod surface under different flow and heat transfer conditions are quantitatively analyzed and compared. The experimental results indicate that increasing the heat flux would increase the near-wall velocity gradient and decrease the temperature gradient. The buoyancy increases with the increase of the heat flux, reducing the turbulent fluctuation in the channel, thereby weakening the generation and diffusion of the turbulent vortex. The dimensionless velocity distribution is obtained by fitting the experimental data to the Spalding formula. Based on the structure of the boundary layer, the increase of buoyancy significantly reduces the proportion of the logarithmic law layer in comparison to the inner layer of the boundary layer. This weakens the convective heat transfer in the channel. The increase of the Reynolds number increases the turbulent fluctuation in the channel and weakens the influence of the buoyancy. Thus, under constant heat flux, the increase of the Reynolds number increases the proportion of the logarithmic law layer in comparison to the inner layer, which enhances the convective heat transfer in the channel.

Combined effect of bridge piers and floodplain vegetation on main channel hydraulics

Different complex flow fields like down-flow, horseshoe vortex, wake vortices and bow waves are generated due to the interaction of approach flow with bridge piers. Scientific researches around bridge piers with floodplain vegetation presents the multilevel fluid dynamics. This allows understanding the interactions of bridge pier and heterogeneous vegetation cover on the river corridor with the flow field of a stream channel. The present study experimentally investigated a three-dimensional turbulent flow field in the main channel of the river with the combined effect of bridge pier and floodplain vegetation. Further, the presence of a single large diameter pier with floodplain vegetation increases the main channel velocity up to 36% compared to no-obstruction on the floodplain. For the same case, the length of the vortex is more, and its strength is two times more than the double pier of smaller diameter. This reveals that the secondary vortex grows its size and strength in the large diameter pier. Furthermore, the convergence induced contraction of the curved channel along with the bridge pier on its floodplain solely affects the turbulent structures in the mainstream of the channel. The experiments associated with the pier diameter and number of piers placed on the floodplain will be notable in understanding flow behavior. In addition, for river ecosystem restoration, the notion of pier diameter, number of piers, and floodplain vegetation should be included in the design practice.

The extended H i halo of NGC 4945 as seen by MeerKAT

ABSTRACT Observations of the neutral atomic hydrogen (H i) in the nuclear starburst galaxy NGC 4945 with MeerKAT are presented. We find a large amount of halo gas, previously missed by H i observations, accounting for 6.8 per cent of the total H i mass. This is most likely gas blown into the halo by star formation. Our maps go down to a 3σ column density level of 5 × 1018 cm−2. We model the H i distribution using tilted-ring fitting techniques and find a warp on the galaxy’s approaching and receding sides. The H i in the northern side of the galaxy appears to be suppressed. This may be the result of ionization by the starburst activity in the galaxy, as suggested by a previous study. The origin of the warp is unclear but could be due to past interactions or ram pressure stripping. Broad, asymmetric H i absorption lines extending throughout the H i emission velocity channels are present towards the nuclear region of NGC 4945. Such broad lines suggest the existence of a nuclear ring moving at a high circular velocity. This is supported by the clear rotation patterns in the H i absorption velocity field. The asymmetry of the absorption spectra can be caused by outflows or inflows of gas in the nuclear region of NGC 4945. The continuum map shows small extensions on both sides of the galaxy’s major axis that might be signs of outflows resulting from the starburst activity.

A New Method for the Reconstruction of Strongly Lensed Galaxies with Resolved Kinematics

Abstract Integral field spectroscopy of high-redshift galaxies has become a powerful tool for understanding their dynamics and evolutionary states. However, in the case of gravitationally lensed systems, it has proved difficult to model both lensing and intrinsic kinematics in a way that takes full advantage of the information available in the spectral domain. In this paper, we introduce a new method for pixel-based source reconstruction that alters standard regularization schemes for two-dimensional (2D) data in a way that leverages kinematic information in a physically motivated but flexible fashion, and that is better suited to the three-dimensional (3D) nature of integral field data. To evaluate the performance of this method, we compare its results to those of a more traditional 2D nonparametric approach using mock Atacama Large Millimeter/submillimeter Array (ALMA) observations of a typical high-redshift dusty star-forming galaxy. We find that 3D regularization applied to an entire data cube reconstructs a source’s intensity and velocity structure more accurately than 2D regularization applied to separate velocity channels. Cubes reconstructed with 3D regularization also have more uniform noise and resolution properties and are less sensitive to the signal-to-noise ratio of individual velocity channels than the results of 2D regularization. Our new approach to modeling integral field observations of lensed systems can be implemented without making restrictive a priori assumptions about intrinsic kinematics, and opens the door to new observing strategies that prioritize spectral resolution over spatial resolution (e.g., for multiconfiguration arrays like ALMA).

The model of radar observation of the surface vibration waves generated by earthquake source (ground vibrator)

This research article is continuation case study based on a model of radar monitoring of vibration waves occurring on the sea surface near the source of a bottom earthquake. The vibration wave is generated parametrically, has near (hydrodynamic) and far (sound) components. The amplitude of the near (generating) wave depends on the bottom vibrator parameters and the depth of the bottom, the far wave propagates in the waveguide formed by the surface and the flat bottom. The vibrator will be installed at a shallow depth (30 m) and the modern aircraft radar will be used to create amplitude and velocity radar images during the experiment. The length of the generated vibration wave will be ~1.5 cm, which corresponds to the frequency of the generating wave ~30 Hz and the “resonant” wave of the radar with a length of ~3 cm (radar X-band). The possibility of monitoring vibration waves in the amplitude and velocity channels of the SAR (synthetic aperture radar) in L, P and UHF-bands is estimated. Also, the expected view of the SAR images is shown. Calculations of the necessary parameters of the aircraft radar are provided, including algorithms for processing the initial signal when creating amplitude and velocity radar images of vibration waves.

Scientific foundations of the movement of components of grain material with an artificially formed distribution of air velocity

The article examines the study of the separation of grain materials in pneumatic channels with an artificially generated distribution of air velocity in the cross-section channel to determine the rational form and parameters of the material supply and options for grain material separation into fractions. The regularities of the weevil movement were theoretically investigated and established in the form of mathematical models of the dynamics of the movement of a solid particle in airflow, which differ from the known ones by taking into account the action of lateral forces, the concentration of the material, and the use of a power-law and an artificially formed exponential law of air distribution facilitated to increase the differences (splitting) trajectories of caryopses by 20 %. The solution of the system of nonlinear differential equations with initial conditions is performed in the Mathcad software environment in the form of trajectories of the grain in the air flow. It allows calculating their trajectories, which differ in windage coefficients and determine the rational values of the parameters of pneumo-gravity and pneumo-inertia separators. Using the obtained dependencies for the development of air separators contributes to determine the initial speed of entry and the direction of entry of the kernels into the airflow, as well as to determine the trajectories of material movement in the air channels with the bottom unloading of material.

Characterization of the Flow and Surface Temperature Around Multiple Vortex Generators

AbstractAn experimental investigation was carried out to study the effects of single and multiple vortex generators (VGs) on the mean velocity, turbulence levels, and surface temperature distributions in a square channel. The flow and heat transfer in the wake of VGs were characterized using particle image velocimetry (PIV) and infrared (IR) thermography. Measurements were performed in the wake regions of VGs, where the counter-rotating vortex pairs (CVPs) were dominant. Inclination angle and taper angle of VGs, spacing-to-width ratio (STW), and streamwise spacing between rows of VGs (S) were varied to understand the effects on flow and heat transfer characteristics. Results reveal a distinct impact of the VGs and layouts on the vortical flow and local convective heat transfer phenomena. The measurements clearly show that configuration parameters such as inclination angle, spacing-to-width ratio, streamwise spacing, and arrangement of multiple VGs are factors in the optimum heat transfer performance applicable to a wide range of thermal management systems.

Simulation of scour and deposition in the flow field and adaptability of fishes around eco-friendly notched groins

Over the past few decades, eco-friendly channel construction has gained wide attention around the world including China, as it considers both navigational and ecological functions. The Groin system is a hydraulic structure that can effectively increase the area of fish habitats. Groin shape has an influence on the local flow field and the scour and deposition pattern near the structure, thereby affecting the adaptability of fishes to the groin fields. In this study, a new groin structure with a notch in its middle part was proposed. A lab experiment was conducted on a physical model to investigate the characteristics of the flow field including patterns of water level distribution, flow velocity distribution, and scour and deposition on different submergence levels and incoming flows. This experiment used four notch depths: 0 (unnotched), 1/3 of groin height, 2/3 of groin height, and full groin height. Then the distribution of habitat suitability index (HSI) was calculated based on the assessment index system of the indicator fish species (Cyprinidae). The results showed that the notches created in the middle of localized overflow groins had a significant effect on the surrounding flow pattern. Due to localized overflow, both the flow velocity and the velocity gradient behind each groin increased. The flow velocity behind each groin was positively correlated with notch depth, while the flow velocity in the main channel was negatively correlated with notch depth. Under the complex flow conditions, depositional features did not occur along the edges of the groin fields, ensuring connectivity between groin fields and the main channel. An analysis of water depth and flow velocity suitability indexes of Cyprinidae suggests when notch depth is 2/3 of groin height, the notched groins have good ecological effects, especially in the groin fields.

Research and application of hydrodynamics modeling of channel in reservoir area-Case of Feilaixia station to Qingyuan station section

In navigable rivers, channel depth and current are the main influencing factors of channel environmental risk, ship navigation mainly relies on channel maintenance water depth information regularly issued by channel departments as guidance, but the long forecast interval limits the full utilization of channel resources to a certain extent. In this paper, by studying the characteristics of the channel from Feilaixia to Qingyuan reservoir area, established the terrain model mesh for the section of the study area, and the two-dimensional shallow water equations are constructed as the control equations of flow simulation. The Model parameters are calibrated and verified. The typical schemes of the channel in the study area were simulated to obtain the channel water depth and velocity information, and the results were visualized, analyzed and discussed. Using two-dimensional hydrodynamic model to simulate channel conditions and calculate flow conditions can provide data support for ship navigation, which has important practical significance for improving navigation management ability.

Convective Acceleration in Porous Media

Convective acceleration occurs in porous media flows due to the spatial variations of the nonuniform flow channel geometry of natural pores. This article demonstrates that the influence of convective acceleration in a nonuniform a pore channel is analogous to that of a constricting pipe channel. Their fluid mechanical behaviour can be comparable, provided that their geometrical characteristics are described precisely in the same manner, and from the same point of reference with regards to the fluid velocity in the flow channels. The analogy of the dissipation mechanisms in nonlinear porous media flow to the "minor loss" approach in fluid mechanics of pipes is therefore appropriate. Conventional nonuniform pipe channel geometries obtain dissipation coefficients within the range 0 < CKL < 0.2. These pipe geometries are relevant reference points for natural porous media, and it is thus expected that most natural pore geometries will obtain values within this range. This assumption holds true for the nine different 3D porous media samples presented here. However, the results show that the rate of change in the pore geometry, and consequently the magnitude of induced convective acceleration, depends on: the area ratio a of the pore channel, the angle of approach θ and the rounding of the pore channel geometry. The rounding of the pore channel reduces the dissipation coefficient, as the rate of change becomes smoother along the channel length. The results also indicate that the pore tortuosity increase the magnitude of nonlinear dissipation, in good agreement with pipe flow behaviour. This knowledge can help improve our interpretation of experimental data and enhance the predictability of porous media equations that incorporate the appropriate dissipation coefficients CKL as a variable.Article HighlightsThe analogy of porous media flow to the "minor loss" approach in fluid mechanics of pipes is appropriate, and the angle of approach θ and the area ratio a of the pore channel govern the magnitude of induced convective acceleration in porous mediaThe rounding of the pore channel geometry reduces the magnitude of induced convective accelerationThe tortuosity of a pore influences the dissipation coefficient CKL and increase the magnitude of induced convective acceleration

Intertidal wetland geomorphology influences main channel hydrodynamics in a mature barrier estuary

Previous research utilising water level observations and hypsometric data has suggested that intertidal areas exert some control on main channel flow dynamics in estuaries, lagoons and tidal creeks. This has been demonstrated in more detail for saltmarsh and mangrove creeks utilising measurements of tidal velocity. However, understanding of relationships between tidal hydrodynamics and intertidal wetlands is still lacking for mature barrier estuaries. Improved understanding of hydrodynamics in these systems, as well as potential interactions with tidal wetlands, may facilitate their effective management and modelling.This study investigates relationships between main channel hydrodynamics and vegetated intertidal wetlands at Minnamurra River estuary, southeast Australia, using observations of tidal dynamics and wetland inundation regime. Tidal data was collected over five spring-neap cycles utilising tidal gauges and drag-tilt flow meters at six locations in the estuary's main channel, and 14 pressure transducers along three wetland transects. Comparison of stage-velocity plots and hypsometric curves indicates that estuarine flow dynamics were spatially variable and strongly influenced by the geomorphology of intertidal wetlands in the upper estuary, where water surface gradients developing during flood and ebb phases created velocity pulses. Spatiotemporal analysis of tidal asymmetry showed variability along the estuary, as well as between spring and neap conditions. The estuary studied displayed an ebb-dominated deeper main channel (velocity asymmetry) surrounded by wide shallow flood-dominated margins, indicating that caution should be adopted when interpreting an estuary's tidal asymmetry using a single asymmetry characteristic.Overall, results presented here demonstrate a strong connection between estuarine hydrodynamics and vegetated intertidal wetlands, which implies that integrated approaches considering estuarine hydrodynamics and vegetated intertidal wetlands simultaneously are required to manage and model mature barrier estuaries.