Hydraulic Conveyance Research Articles

Study on the hydraulic conveyance characteristics of suspended coarse particles within pipelines

The Flow Regime Transition Device transforms the gelled crude oil mass into gelled crude oil particles for hydraulic conveying. The gelled crude oil particles may reaggregate into gelled crude oil mass at the later stage of hydraulic conveying. Therefore, understanding the patterns of hydraulic suspension conveying gelled crude oil particles is vital for safely gathering and efficiently conveying crude oil. This paper employs the CFD-DEM coupling technique to conduct a numerical study on the hydraulic conveying characteristics of gelled crude oil particles. The accuracy of the model and the solution method is verified by comparing them with the experimental data of particle concentration distribution, and single particle rise behavior, and particle transport flow of gelled crude oil. The size range of gelled crude oil particles spans from 0.0001 m to 0.003 m. We operate the transportation within a velocity range of 0.5 to 4 m/s and a concentration range of 0.022 to 0.0537. Simulation results indicate two flow regimes in the hydraulic conveying of gelled crude oil particles: an upper-moving bed flow and a heterogeneous suspension flow. With increased conveying velocity, the upper moving bed flow gradually transitions to a heterogeneous suspension flow. Beneath the upper moving bed flow, some scattered particles exist, likely resulting from the action of turbulent diffusion. Changes in conveying concentration and particle size have a minor impact on the velocity distribution of particles and fluid but a more significant effect on the particle distribution across the pipe cross-section. Also, when conveying particles of different sizes, most smaller particles travel along the pipe wall.

Design of a Stormwater Management System in Lady Irene Campus

This project aimed to design an efficient drainage system for Ndejje University's Lady Irene Campus, addressing issues of erosion and flooding exacerbated by recent construction projects. The goal was to create a hydraulic conveyance system that balances environmental protection with structural integrity and affordability. The project involved field reconnaissance, data collection, and analysis of the campus's landscape, soil types, and development trends to inform the design. Methodologically, the project used GPS surveying to create topographical maps and obtained rainfall data to size drainage facilities using the rational method. The peak runoff was calculated considering land use characteristics, while Manning’s formula was applied to design drainage channels and culverts. The design aimed to ensure high hydraulic capacity and prevent erosion with specific slope and material choices. An Environmental Impact Assessment was conducted, addressing noise, dust, water quality, waste management, and ecological impacts. Mitigation measures were recommended to minimize adverse effects during the construction and operation phases. Despite challenges such as limited access to surveying equipment and data, the project concluded with a comprehensive stormwater management plan. Recommendations include rehabilitating the university’s weather station and establishing a project database to support future planning and research. The project underscores the importance of integrating sustainable practices in urban development to safeguard environmental and infrastructural integrity.

Modifying physical supply and use tables (PSUTs) in the system of environmental-economic accounting (SEEA) for off-farm irrigation water management

A reliable water accounting framework is crucial for understanding the contribution of water resources in meeting agricultural demands and selecting appropriate operating systems for off-farm water systems, including hydraulic conveyance and distribution structures. This ensures fair, adequate, and dependable irrigation water distribution, especially under water scarcity operational scenarios. This study presents a novel and effective method for modifying PSU tables in the SEEA water accounting framework that is specifically designed for small-scale agricultural water management study areas. The proposed approach entails a comprehensive analysis of the surface water distribution within the water holders using a hydraulic simulation model and a spatial analysis of the groundwater extraction for meeting on-farm water demands. This approach was implemented on Iran's Central Plateau and revealed notable variations in water rights and distribution effectiveness among stakeholders so that, surface water contributed 27–40% less than the legal water rights, leading to aquifer overexploitation. The evaluation indicated that changing crop patterns and upgrading to pressurized irrigation systems led to 4–7.5% overexploitation of groundwater and 3.5–6% water conservation on farm scales. Besides, the spatial assessment verified a considerable overlap of 59% between the farms with modern irrigation systems and those with cultivated area expansion, resulting in sustained overexploitation pressure on the aquifer. The present study has two significant practical implications. Firstly, it specifies the contribution of surface- and groundwater resources in fulfilling the water demands of individual water-holders. Secondly, it provides reliable information to decision-makers about the incentives for modernization, rehabilitation, and renovation projects in an irrigation district.

Insight into heterogeneous karst catchment by the dynamical system approach

The hydrological process heterogeneity in karst catchments makes collecting sufficient information about the karst system properties extremely difficult. Consequently, the parameterization and application of currently available modeling approaches is highly uncertain in karst. We implemented a modified dynamical system approach and explored the possibilities to analyze, simulate and characterize karst springs and sinking streams in the heterogeneous Ljubljanica river catchment in Slovenia. The discharge sensitivity functions were used to simulate the hydrographs and identify the differences in the temporal dynamics of the discharge recession. Most of the derived karst springs and sinking streams discharge sensitivity functions express dual discharge recession behavior most likely controlled by the hydraulic conveyance characteristics of karst underground conduits. The implemented approach offers a high potential for advancement in karst hydrology by using basic discharge data for analyses of karst catchment characteristics and future planning of karst water resource management.

Measurements of capture cross-section of 93Nb by activation method and half-life of 94Nb by mass analysis

ABSTRACT The thermal-neutron capture cross section (σ 0 ) and resonance integral (I 0 ) for93Nb were measured by an activation method; a half-life of 94Nb was derived by mass analysis. Niobium-93 samples were irradiated with the use of the hydraulic conveyer installed in the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Gold-aluminum and cobalt-aluminum alloy wires were used to monitor thermal-neutron fluxes and Westcott’s indexes at the irradiation position. A 25-μm-thick gadolinium foil was used to separate reactions ascribed to thermal neutrons. Its thickness provided a cut-off energy of 0.133 eV. In order to attenuate the radioactivity of 182Ta produced by impurities, the Nb samples were cooled for nearly 2 years. The induced radio activity in the monitors and Nb samples was measured by gamma-ray spectroscopy. In the analysis based on Westcott’s convention, the σ 0 and I 0 values were calculated as 1.11 ± 0.04 barns and 10.5 ± 0.6 barns, respectively. After the γ-ray measurements, mass analysis was applied to the Nb samples to obtain the reaction rate. By combining data obtained by both γ-ray spectroscopy and mass analysis, a half-life of 94Nb was determined as (2.00 ± 0.15) ×104 years.

A novel methodology to quantify hydraulic conveyance through an ice-impacted lake-outlet system

River ice can pose considerable challenges to hydropower operations in cold regions. Relative to open-water conditions, the presence of ice in various forms contributes to lower hydraulic efficiency. At the outlet of Lake Winnipeg, maintaining winter conveyance through the channels of the Outlet Lakes Area (OLA) is of paramount importance for downstream energy production on the Nelson River. The complex hydraulic conditions of the OLA are attributed to various factors, including the influence of hydraulic system operation, flow routing through lakes and rivers with non-uniform attributes, and the presence of dynamic ice processes throughout winter. In this study, a methodology was designed to quantify the impacts of ice on the OLA hydraulics using a combination of numerical modelling and statistical techniques. This approach includes adaptation and configuration of a two-dimensional river ice model, selection of suitable performance metrics, and derivation of hydraulic datasets for model simulations using historical observations and statistical relationships. Numerical modelling simulations feature treatments for predominant ice processes in the OLA, including freeze-up jamming, thermal growth and decay of a stable ice cover, and under cover transport and deposition of brash ice. The methodology was evaluated using historical winters 1996–1997 to 2020–2021, with most results falling within an acceptable performance range, even in response to varying hydro-meteorological conditions. Instances of error exceeding accepted thresholds were attributed mainly to factors outside of the study, including uncertainty in discharge estimation and the effects of mid-winter forebay operation. Influence of Lake Winnipeg water levels on winter hydraulics was identified as significant, as higher upstream Lake Winnipeg water levels can mitigate ice impacts by providing more hydraulic head for conveyance. As expected, ice restriction severity also varies in accordance with heat fluxes. Targeted areas for improvement of the methodology and future work are discussed, including enhancing the simulation of the thawing (‘pre-breakup’) period and field verification of flow split quantities during winter. The methodology presented provides an estimate of ice-impacted hydraulic conveyance which serves to benefit hydropower operators, regional water resources studies, and further investigations of river ice impacts that can be attributed to future climate change.

Velocity uncertainty quantification based on Riparian vegetation indices in open channels colonized by Phragmites australis

One of the main purposes of Ecohydraulics is to predict the effects of riparian vegetation on aquatic ecosystems within real water channels. The interaction between water flow and riparian plants significantly affects flow dynamics, hydraulic conveyance, and water quality of vegetated water bodies. This study aimed at quantifying analytically the uncertainty in flow average velocity estimations associated with the uncertainty of Leaf Area Index (LAI) of Phragmites australis (Cav.) Trin. ex Steudel covering a vegetated channel. The impacts of this species on the hydrodynamics of vegetated streams are far to be completely understood. The uncertainty in flow average velocity was assessed through the first-order second-moment statistical method, by comparing direct and indirect LAI measurements of mature Phragmites australis plants. Indirect LAI values were obtained using the LICOR® LAI-2000 Plant Canopy Analyzer device. The results of this study suggest that the uncertainties in flow average velocity estimations are comparable to those associated with experimental measurements of streamwise velocity components retrieved in real vegetated flows fully covered by mature Phragmites australis plants.

Bulk Drag Predictions of Riparian Arundo donax Stands through UAV-Acquired Multispectral Images

Estimating the main hydrodynamic features of real vegetated water bodies is crucial to assure a balance between their hydraulic conveyance and environmental quality. Riparian vegetation stands have a high impact on vegetated channels. The present work has the aim to integrate riparian vegetation’s reflectance indices and hydrodynamics of real vegetated water flows to assess the impact of riparian vegetation morphometry on bulk drag coefficients distribution along an abandoned vegetated drainage channel fully covered by 9–10 m high Arundo donax (commonly known as giant reed) stands, starting from flow average velocities measurements at 30 cross-sections identified along the channel. A map of riparian vegetation cover was obtained through digital processing of Unnamed Aerial Vehicle (UAV)-acquired multispectral images, which represent a fast way to observe riparian plants’ traits in hardly accessible areas such as vegetated water bodies in natural conditions. In this study, the portion of riparian plants effectively interacting with flow was expressed in terms of ground-based Leaf Area Index measurements (LAI), which easily related to UAV-based Normalized Difference Vegetation Index (NDVI). The comparative analysis between Arundo donax stands NDVI and LAI map enabled the analysis of the impact of UAV-acquired multispectral imagery on bulk drag predictions along the vegetated drainage channel.

Assessment of Riverine Dredging Impact on Flooding in Low-Gradient Coastal Rivers Using a Hybrid 1D/2D Hydrodynamic Model

The current study investigates the effect of large-scale channel modifications via riverine dredging on flood dynamics in low-gradient river systems located in inland-coastal flood transition zones. The study site is the Vermilion River in south Louisiana, US, which is characterized by complex flow regimes, reversal and bi-directional flows, presence of large swamps with significant river-swamp interactions, and large volumes of runoff contributions from lateral tributaries. The study aims to understand the interplay of these factors and how they modulate and get affected by different dredging approaches that vary in spatial extent and the modifications introduced to the channel. The study deploys a hybrid, one-/two-dimensional (1D/2D), hydrodynamic model that simulates flow and stage dynamics in the main river and its major tributaries, as well as the flow exchanges with the interconnected swamp system. Overall, the results show that the dredging activities can significantly alter the flow regime in the watershed and affect flow exchanges between the river and the swamp system. In terms of flooding impact, only dredging approaches that are extensive in spatial extent and modifications to channel longitudinal slope can result in sizeable reductions in flood stages. However, these benefits come at the expense of significant increases in the amplitude and inland propagation of the Gulf tidal wave. On the other hand, less-extensive dredging can still provide moderate and spatially limited flood mitigation; however, they further expose downstream communities to increased levels of flooding, especially during more frequent events. The results reveal that while dredging can increase the hydraulic conveyance of the river system, the large runoff volumes delivered by the urbanized tributaries seem to outweigh the added improvement in the in-channel storage, thus reducing the anticipated flood relief. The results suggest that a watershed-centered approach, instead of a riverine-centered approach is needed for flood management in these systems so that the relative benefits and tradeoffs of different mitigation alternatives can be examined.

Experimental Study on Hydraulic Conveying Characteristics by Discharging Plates for Sediment Removal

Experimental Study on Hydraulic Conveying Characteristics by Discharging Plates for Sediment Removal

Thermal-neutron capture cross sections and resonance integrals of the 243Am(n,γ)244gAm and 243Am(n,γ)244m+gAm reactions

ABSTRACT The thermal-neutron capture cross sections (σ0) and resonance integrals (I0) were measured for the 243Am(n,γ)244gAm and 243Am(n,γ)244m+gAm reactions by a neutron activation method. Americium-243 samples were irradiated with a pneumatic tube and a hydraulic conveyer installed in the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Alloy wires of Au/Al, Co/Al or Co foils were used as neutron monitors to measure thermal-neutron fluxes and epi-thermal Westcott’s indexes at irradiation positions. A 25-μm-thick gadolinium foil was used to separate reactions due to thermal- and epi-thermal neutron components, and a value of 0.133 eV was taken as a corresponding cut-off energy. Gamma-ray spectroscopy was applied to measure radioactivity of neutron monitors and the ground state of reaction products, while alpha-ray spectroscopy was applied to measure that of target 243Am and final reaction product 244Cm through the decay of 244m, 244gAm. By utilizing Westcott’s convention, the σ0 and I0 values were derived as 4.73 ± 0.27 barn and 96.5 ± 8.9 barn for the 243Am(n,γ)244gAm reaction, and 88.5 ± 4.0 barn and 2.30 ± 0.20 kilobarn for the 243Am(n,γ)244m+gAm reaction, respectively. The present result of σ0 for the production of 244m+gAm agreed with the reported value of 87.7 ± 5.4 barn measured with a time-of-flight method within the limits of uncertainties.

Sedimentation and erosion patterns within anabranching channels in a lowland river restoration project

ABSTRACT Anabranching channel designs are seldom utilized for river restoration projects despite their potential for efficient hydraulic conveyance and robust floodplain habitat. We evaluated a stream restoration project that concentrates base flows within a single deep, narrow channel overflowing into secondary channels and an alternating series of higher elevation active benches at flood stages. The design represents an implementation of a Cluer and Thorne SEM Stage 8 anastomosing system aimed at increasing transport efficiency of water and sediment through low gradient river reaches to alleviate flooding on adjacent properties. We investigated the performance of the project’s hydraulic conveyance and the general utility of anabranching channels as a restoration alternative by assessing the distribution and magnitude of deposition and erosion response patterns. High-resolution survey indicate aggradation is not occurring within the main channel. Between summer 2016 and summer 2017, reaches experienced mean elevation decreases between 0.08 and 0.29 m indicating effective discharge rates transported dominant grain sizes. Along some reaches, bed scour was sufficient to undercut banks, producing slumps, which may affect long-term conveyance capacities. Lateral bank scour was limited to reaches exposed to daily tidal flows. Variable deposition patterns were observed within secondary channels, depending on cumulative precipitation, dominant hydrology, and channel entrance orientation. Isolated tidal flows resulted in deposition, while long duration flood flows produced intertidal floodplain scour. Within fluvially-dominated benches, uniform longitudinal deposition of fine-grained sediments was associated with low channel entrance flow rates. Higher entrance flow rates resulted in concentrated deposition of coarse-grained particles, up to 0.21 m, and a longitudinal gradient of decreasing sediment sizes and magnitude. This study builds upon previous work by providing a high-resolution assessment of a constructed anabranching channel system and confirms its suitability for efficient hydraulic conveyance within fluvial reaches of lowland rivers and provides general recommendations for future designs.

Rheological Behavior of Fly Ash Suspension with Additive for Hydraulic Conveyance

In the present work, rheological behaviour of a fine particulate fly ash slurry suspension is studied with and without addition of an additive. Rheological experiments are performed for the range of shear rate from <i>50</i> to <i>200 s</i><i>1</i>. Sodium sulfate is used as an additive in the fraction of <i>0.2</i>, <i>0.4</i> and <i>0.6</i>% (by weight). Addition of sodium sulfate to the fly ash slurry suspension leads to an improvement of its rheological characteristics. A reduction in relative viscosity and pressure drop is more pronounced with the addition of sodium sulfate in proportion of <i>0.4</i>%, while marginal with <i>0.2</i> and <i>0.6</i>% (by weight). The analysis reveals that the fly ash suspension has a potential to for being transported in a slurry pipeline with higher concentration and minimum energy consumption.

Effect of Concentric Annular Gap Flow on Wall Shear Stress of Stationary Cylinder Pipe Vehicle under Different Reynolds Numbers

The tube-contained raw material pipeline hydraulic transportation technology is an optimization and improvement of traditional hydraulic capsule pipeline (HCP) transport. It has the advantages of lower resource consumption, environmental protection, and less demand for human resources and has the ability to directly transport solids, liquids, and gases. The cylinder pipe vehicle is the core component of tube-contained raw material pipeline hydraulic transportation; its motion characteristics and energy consumption are affected by wall shear stress. When the cylinder pipe vehicle is stationary, the annular gap flow will affect the wall shear stress. This paper studies the wall shear stress and annular flow field distribution of a stationary cylinder pipe vehicle under different Reynolds numbers. The results show that as the Reynolds number increases, both the wall shear stress and the annular gap flow velocity show a gradually increasing trend. The wall shear stress and the velocity of the annular gap flow show some correlation, but there are differences in the trend of axial and circumferential wall shear stress along the length of the cylinder pipe vehicle. The research in this article will further improve the theoretical system of hydraulic conveyance of barrel-loading pipelines and provide a theoretical basis for the realization of industrial applications as soon as possible.

Measurements of thermal-neutron capture cross-section of Cesium-135 by applying mass spectrometry

ABSTRACTThe thermal-neutron capture cross-section (σ0) and resonance integral (I0) were measured for the 135Cs(n,γ)136Cs reaction by an activation method and mass spectrometry. Because of difficulty in the preparation of pure 135Cs samples, we used 135Cs contained as an impurity in a normally available 137Cs standard solution. An isotope ratio of 135Cs and 137Cs in a standard 137Cs solution was measured by mass spectrometry to quantify 135Cs. Cesium-135 impurity along with the 137Cs standard solution was irradiated at the hydraulic conveyer of the research reactor in the Institute for Integral Radiation and Nuclear Science, Kyoto University. Wires of Co/Al and Au/Al alloys were used as neutron monitors to measure thermal-neutron fluxes and epi-thermal Westcott’s indices at an irradiation position. A gadolinium filter was used to measure the σ0, and a value of 0.133 eV was taken as the cut-off energy. Gamma-ray spectroscopy was used to measure induced activities of 137Cs, 136Cs and monitor wires. On the basis of Westcott’s convention, the σ0 and I0 values were derived as 8.57 ± 0.25 barn, and 45.3 ± 3.2 barn, respectively. The value of σ0 obtained in the present study agreed within the limits of uncertainties with the past-reported value of 8.3 ± 0.3 barn.

High Pressure Injection of Chemicals in a Gravel Beach

The remediation of beaches contaminated with oil includes the application of surfactants and/or the application of amendments to enhance oil biodegradation (i.e., bioremediation). This study focused on evaluating the practicability of the high pressure injection (HPI) of dissolved chemicals into the subsurface of a lentic Alaskan beach subjected to a 5 m tidal range. A conservative tracer, lithium, in a lithium bromide (LiBr) solution, was injected into the beach at 1.0 m depth near the mid-tide line. The flow rate was varied between 1.0 and 1.5 L/min, and the resulting injection pressure varied between 3 m and 6 m of water. The concentration of the injected tracer was measured from four surrounding monitoring wells at multiple depths. The HPI associated with a flow rate of 1.5 L/min resulted in a Darcy flux in the cross-shore direction at 1.15 × 10−5 m/s compared to that of 7.5 × 10−6 m/s under normal conditions. The HPI, thus, enhanced the hydraulic conveyance of the beach. The results revealed that the tracer plume dispersed an area of ~12 m2 within 24 h. These results suggest that deep injection of solutions into a gravel beach is a viable approach for remediating beaches.

What do pneumatic conveying and hydraulic conveying have in common?

Pneumatic conveying (PC) and hydraulic conveying (HC) have significant applications in various industries. These two methods of conveying differ only by the type of carrier fluid: one is compressible and the other is not. Nevertheless, they are considered very different, attracting different research groups that rarely have a dialog. Therefore, the main objective of this research is to compare both systems, bridge the gap, and establish common analysis principles for both PC and HC. In order to bring both these conveying methods into a common ground, a new feeder based on PC technology is designed and used in HC. Hence, similar phase diagrams are obtained. Additional windows are opened to define future research efforts to conduct PC and HC research with the same tools. In order to do this, the significance of the Archimedes number is introduced in this paper. Furthermore, non-settling flows, more common in HC, are analyzed, and detailed explanations are presented to show that they should also exist in PC, for which they have never been mentioned.

Experimental Study on Hydraulic Conveying Characteristics by Discharging Plates for Sediment Removal

In the hydraulic transportation of solid-liquid flow in the conduits, the authors have proposed that to place the discharging plates in the flow area is valid to transport particles piled up. In the previous paper, we examined the effects of interval length of discharging plates while the plates were used under the experimental condition that was these plates were not inserted particles bed. However, practically the discharging plates have been used under the circumstance that is these plates are inserted particles bed. Therefore, in this paper, we examined the effects of interval length of discharging plates while the plates were used under the experimental condition that was these plates were inserted particles bed. As a result, it was found that the optimum interval length of discharging plates in current installation depth of the discharging plates. In addition, it was revealed by the visualization of particles behavior that the circumstances of the scouring boundary change by the interval length of discharging plates.

Three‐dimensional hydraulic characterisation of the Arno River in Florence

Rivers in historical cities, such as the Arno River in Florence, are typically characterised by unique complex‐shaped hydraulic structures (such as bridges and weirs). The flow interaction with these structures can lead to a fully 3D flow field which cannot be properly investigated with commonly employed 1D, and even 2D, hydraulic models. Nowadays, 3D computational fluid dynamics (CFD) tools can be successfully used in river management context. Florence is characterised by a high risk of flooding and the disastrous consequences of such events being greatly increased due to its inestimable artistic heritage. The main cause of flooding is the limited hydraulic conveyance capacity of the Arno River in Florence due to several complex hydraulic structures along the reach. The present work represents the first 3D hydraulic model of the Arno River in the urban reach of Florence. The geometric model was created using the 3D bed topography of the river surveyed in 2015. The hydraulic model was calibrated and validated using discharge and water stage field data measured in 2016. The 3D model can be used as a more realistic tool for exploring mitigation solutions for the reduction of hydraulic risk.

Evaluation of Soil Saver Walls on Aquatic Organism Passage Through Box Culverts

Abstract Reinforced concrete box culverts are designed to provide hydraulic conveyance at peak stream discharge in a cost-effective manner; however, these structures can promote headcutting. Many state departments of transportation construct soil saver walls or similar structures on the upstream of box culverts to prevent headcutting. These walls act as a drop inlet and may hinder free movement of aquatic organisms. The potential impact on aquatic organism passage has resulted in regulatory pressure to develop alternatives or modifications to the traditional soil saver wall design. This article contains the results of an analysis of the potential impact of box culverts with solid soil saver walls on aquatic organism passage. The results of a survey of thirty states and fifteen field sites on the current state-of-practice for box culverts, and flume tests using model box culverts with a solid soil saver wall and with modified design to promote aquatic passage are presented. Modifications to the soil saver wall design are recommended based on the results of the survey of states, field surveys, and flume testing.