Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(11)
Published: Nov. 1, 2024
Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)
Published: March 1, 2025
This study investigates the hydrodynamics and sediment transport in a double-layered partially vegetated mobile bed channel, focusing on impact of submerged vegetation with submergence ratio 61.53% 30.77% flow dynamics morphology. Experiments were conducted straight, tilting rectangular flume staggered double layered covering half channel width. The three dimensional time-averaged velocity components, turbulent intensities, secondary current, kinetic energy, Reynolds shear stress are measured analyzed using contour plots along outcomes reveal that induces significant momentum exchange between non-vegetated sections. In section, dampens streamwise intensity near bed, promoting deposition enhancing stability. Momentum transfer at interface strengthens shear, increasing turbulence leading to greater erosion. Negative streamwise-vertical indicates helical flow, while transverse-vertical peaks bed. Flow diversion intensifies erosion high-energy vegetation-induced drag decelerates causing transition deeper section. Double-layered rivers or canals is more effective stabilizing materials. These findings provide critical insight for river restoration management, emphasizing necessity integrated management strategies balance across heterogeneous environments.
Language: Английский
Citations
0
Physics of Fluids, Journal Year: 2025, Volume and Issue: 37(3)
Published: March 1, 2025
Accurately predicting the arithmetic mean velocity of overland flows on vegetated slopes is essential for developing hydraulic erosion models. However, there exists a significant challenge in this various vegetation conditions. This study proposed new predictive model based principle resistance superposition, which accounted wide range environmental factors—e.g., coverage, slope angle, and flow discharge. The was validated against comprehensive database with 4168 datasets established from published sources, showing 83.3% calculated R squared values excess 0.750. also compared existing models, demonstrating superior applicability reliability at test After validation comparison, parametric analysis conducted to assess effects factors velocity. results highlighted that decreased increasing coverage until reaching limit strong interactive these These findings provide valuable insights into how influence velocity, offering theoretical foundation control slopes.
Language: Английский
Citations
0
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(3)
Published: March 1, 2024
Marine sponges influence the flow hydrodynamics by suction/pumping mechanism. They provide a recirculation and remove pollutants from their residence. Previous studies have validated efficacy of mimetic in improving momentum transfer marine environments. This study endeavors to explore impact wave characteristics (i.e., height period) on near sponges. Both physical numerical simulations were undertaken this phenomenon. Experimental results unveiled that efficiency sponge is contingent upon some circumstances. When waves short period height, suction effects prevail. In such cases, orbital velocity tends be negative direction, leading suppressed fluctuating velocities reduction turbulent kinetic energy throughout water column. Thus, penetration shear layer column occurrence wake-street diminish. Conversely, an increase enhances exchange through Surface Line Integral Convolution Three-Dimensional stream trace visualizations using OpenFOAM insights into generation spirals vortices induced
Language: Английский
Citations
2
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(9)
Published: Sept. 1, 2024
Meandering compound channels, which are the most common platform acquired by natural rivers, typically equipped with vegetated floodplains that exhibit complex hydraulic characteristics and sediment transport processes. Given studying depth-averaged streamwise velocity is foundation for determining flood discharge performance carrying capacity, this paper presents an analytical solution to forecast lateral distribution in meandering channels floodplains. The model, incorporates effects of bed friction, vegetation-induced drag force, transverse shear turbulence, secondary flows, derived from longitudinal depth-integrated Navier–Stokes equation continuity assuming current term additional Reynolds stress be laterally linear. proposed model then successfully applied curved different reported literature. satisfactory agreement between predicted experimental results validates effectiveness model. Thereafter, impact varying characteristic parameters on profile discussed analyzed applying validated Results indicate coefficients dimensionless eddy viscosity exert more pronounced influences than associated vegetation-triggered force. Furthermore, it found sizes signs contingent upon intensities rotational directions flow cells. presented can employed as alternative methodology gain insight into rivers
Language: Английский
Citations
2
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(11)
Published: Nov. 1, 2024
A mathematical model based on advection-diffusion theory is established to study the non-equilibrium sediment transport process in vegetated channels. The effects of vegetation velocity distribution and diffusion coefficients were considered, respectively. Validation against experimental data from flume studies confirms model's ability accurately predict longitudinal deposition rate vertical suspended concentration (SSC). comparative analysis three coefficient formulations indicates that linear-exponential formula provides a more precise estimate εsz, performs well predicting turbulent both rigid flexible when gently swaying. Moreover, distance required for SSC regain equilibrium influenced by submergence level canopy. At lower levels, canopy shear vortices significantly affect exchange sediment, exhibit pronounced stratification near An increase density at these levels intensifies vortices, thereby extending needed reach equilibrium. higher impact lessened, which reduces characteristics, flow similar rough boundary layer flow. increases resistance, shortens attain However, further efforts are explore characteristics with highly motion grain size non-uniform sediments flows.
Language: Английский
Citations
2
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(3)
Published: March 1, 2024
Airborne chemical species transport and adsorption in the crown of trees are relevant processes with many crucial environmental consequences. This multiphase multiscale process requires incorporation momentum both air solid phases composing biomass (leaves branches) coupling mass transport. In this work, an upscaled model for tree crowns is derived using method volume averaging. The comprises four effective-medium equations, namely: macroscopic balance equation air, which has a Darcy-like structure; equations total transport, considering deformable leaves branches; unsteady (diffusive convective) at surface branches. These written terms coefficients that capture essential microscale information by solving ancillary closure problems periodic unit cells Laplace domain. allowed evaluating dynamic functionality dispersion Reynolds number, velocity rate. predictions average concentration were found to be excellent agreement direct numerical simulations (i.e., relative percent difference smaller than 1%), thus providing first validation model. Extensions other systems briefly discussed.
Language: Английский
Citations
1
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(9)
Published: Sept. 1, 2024
The performance of turbulence models was investigated to predict the flow and features vegetated channel using computational fluid dynamics (CFD). Ansys Fluent, CFD software implemented for numerical studies. three-dimensional, incompressible, steady, turbulent. Ten models, provided by were comparative study. model validated against an experimental study conducted in literature. studies show that Renormalization group k–ε is most successful predicting characteristics with a Root Mean Square Error (RMSE) value 0.2752. At same time, Reynolds Stress Model gives least predictive performance, indicated RMSE 0.4302. Moreover, Spalart–Allmaras (S–A) offers shortest computation time 6652.393 s, whereas Shear Transport k–ω proves be time-consuming 11 952.219 s. velocity water not uniform as it slower at surface leaves faster free zones. maximum observed middle section channel, below leaf, between roots u = 0.1158 m/s. Furthermore, are influenced several factors such geometry, velocity, vegetation distribution. As result, presence affects significantly.
Language: Английский
Citations
0
Physics of Fluids, Journal Year: 2024, Volume and Issue: 36(11)
Published: Nov. 1, 2024
Citations
0