Journal articles: 'Hydraulisk modell'

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Christoffersen, Bradley O., Manuel Gloor, Sophie Fauset, Nikolaos M. Fyllas, David R. Galbraith, Timothy R. Baker, Bart Kruijt, et al. "Linking hydraulic traits to tropical forest function in a size-structured and trait-driven model (TFS v.1-Hydro)." Geoscientific Model Development 9, no. 11 (November 24, 2016): 4227–55. http://dx.doi.org/10.5194/gmd-9-4227-2016.

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Abstract. Forest ecosystem models based on heuristic water stress functions poorly predict tropical forest response to drought partly because they do not capture the diversity of hydraulic traits (including variation in tree size) observed in tropical forests. We developed a continuous porous media approach to modeling plant hydraulics in which all parameters of the constitutive equations are biologically interpretable and measurable plant hydraulic traits (e.g., turgor loss point πtlp, bulk elastic modulus ε, hydraulic capacitance Cft, xylem hydraulic conductivity ks,max, water potential at 50 % loss of conductivity for both xylem (P50,x) and stomata (P50,gs), and the leaf : sapwood area ratio Al : As). We embedded this plant hydraulics model within a trait forest simulator (TFS) that models light environments of individual trees and their upper boundary conditions (transpiration), as well as providing a means for parameterizing variation in hydraulic traits among individuals. We synthesized literature and existing databases to parameterize all hydraulic traits as a function of stem and leaf traits, including wood density (WD), leaf mass per area (LMA), and photosynthetic capacity (Amax), and evaluated the coupled model (called TFS v.1-Hydro) predictions, against observed diurnal and seasonal variability in stem and leaf water potential as well as stand-scaled sap flux. Our hydraulic trait synthesis revealed coordination among leaf and xylem hydraulic traits and statistically significant relationships of most hydraulic traits with more easily measured plant traits. Using the most informative empirical trait–trait relationships derived from this synthesis, TFS v.1-Hydro successfully captured individual variation in leaf and stem water potential due to increasing tree size and light environment, with model representation of hydraulic architecture and plant traits exerting primary and secondary controls, respectively, on the fidelity of model predictions. The plant hydraulics model made substantial improvements to simulations of total ecosystem transpiration. Remaining uncertainties and limitations of the trait paradigm for plant hydraulics modeling are highlighted.

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Guo, Xiao Le, Zhi Ming Wang, and Zhi Hui Long. "Hydraulics Analysis System for Extended Reach Drilling in China and its Application." Applied Mechanics and Materials 241-244 (December 2012): 1349–53. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.1349.

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The extended reach drilling (ERD) is being adopted widely as an effective and economical way of developing oilfields in China. But it also brought a series of technical difficulties because of its own characteristics. Some progresses were made after several years of hard work in China about Hydraulics for extended reach drilling, which included cuttings transport models and rules, precise model of circulating system pressure loss calculation, hole cleaning calculating models and monitoring method, hydraulic extended limit calculation model and analysis, hydraulics design and optimization method for ERD. Based on the above studies, the author finally developed a system of hole cleaning monitoring and hydraulics design and its risk analysis which could provide theoretical support and useful tool for engineering design and risk assess before drilling. These researches are helpful to ERD and have enriched the hydraulic theory of ERD.

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Vanderborght, Jan, Valentin Couvreur, Felicien Meunier, Andrea Schnepf, Harry Vereecken, Martin Bouda, and Mathieu Javaux. "From hydraulic root architecture models to macroscopic representations of root hydraulics in soil water flow and land surface models." Hydrology and Earth System Sciences 25, no. 9 (September 6, 2021): 4835–60. http://dx.doi.org/10.5194/hess-25-4835-2021.

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Abstract. Root water uptake is an important process in the terrestrial water cycle. How this process depends on soil water content, root distributions, and root properties is a soil–root hydraulic problem. We compare different approaches to implement root hydraulics in macroscopic soil water flow and land surface models. By upscaling a three-dimensional hydraulic root architecture model, we derived an exact macroscopic root hydraulic model. The macroscopic model uses the following three characteristics: the root system conductance, Krs, the standard uptake fraction, SUF, which represents the uptake from a soil profile with a uniform hydraulic head, and a compensatory matrix that describes the redistribution of water uptake in a non-uniform hydraulic head profile. The two characteristics, Krs and SUF, are sufficient to describe the total uptake as a function of the collar and soil water potential, and water uptake redistribution does not depend on the total uptake or collar water potential. We compared the exact model with two hydraulic root models that make a priori simplifications of the hydraulic root architecture, i.e., the parallel and big root model. The parallel root model uses only two characteristics, Krs and SUF, which can be calculated directly following a bottom-up approach from the 3D hydraulic root architecture. The big root model uses more parameters than the parallel root model, but these parameters cannot be obtained straightforwardly with a bottom-up approach. The big root model was parameterized using a top-down approach, i.e., directly from root segment hydraulic properties, assuming a priori a single big root architecture. This simplification of the hydraulic root architecture led to less accurate descriptions of root water uptake than by the parallel root model. To compute root water uptake in macroscopic soil water flow and land surface models, we recommend the use of the parallel root model with Krs and SUF computed in a bottom-up approach from a known 3D root hydraulic architecture.

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Guo, Xiao Le, Zhi Ming Wang, and Zhi Hui Long. "Research Progresses of Hydraulics for Extended Reach Drilling in China, Part I: Cuttings Transport and Precise Calculation of Pressure Loss." Advanced Materials Research 524-527 (May 2012): 1557–60. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.1557.

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The extended reach drilling (ERD) is being adopted widely as an effective and economical way of developing oilfields in China. But it also brought a series of technical difficulties because of its own characteristics. Some progresses were made after several years of hard work in China about Hydraulics for extended reach drilling, which included cuttings transport models and rules, precise model of circulating system pressure loss calculation, hole cleaning calculating models and monitoring method, hydraulic extended limit calculation model and analysis, hydraulics design and optimization method for ERD. Based on the above studies, the author finally developed a system of hole cleaning monitoring and hydraulics design and its risk analysis which could provide theoretical support and useful tool for engineering design and risk assess before drilling. These researches are helpful to ERD and have enriched the hydraulic theory of ERD. Due to space limitations, this article could only demonstrate part of these progresses, as the subtitle showed.

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Ndomba, Preksedis M., and Joel Nobert. "Problems and Prospects of Hydraulic Modelling For Environmental Flows Assessment Studies in East Africa." Tanzania Journal of Engineering and Technology 34, no. 2 (December 31, 2013): 67–83. http://dx.doi.org/10.52339/tjet.v34i2.460.

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The objective of this paper is to document the problems and prospects of hydraulic modelling for Environmental Flows Assessment (EFA) studies based on selected case studies. Most of studies in East Africa use Holistic methodologies. An ideal data set for defining river hydraulics for most of these methods would be six data points of stage measurements over a good distribution of discharges, the stage of zero discharge and some flood-related data. Besides, in East African region EFA studies suffer from data scarcity (i.e., poorly gauged sites) and limited expertise and funding. The hydraulics studies conducted by the authors entailed desktop research, limited fieldwork for data collection, data analysis, and modelling. The hydraulic models (HEC-RAS and PHABSIM) used are governed by Manning and/or Energy equation(s) to simulate hydraulics. The optimized sensitive parameters include roughness number, expansion/contraction coefficients,roughness modifier and Beta coefficient. Data collected at medium flow, bank full discharge information at neighbouring flow gauging stations, information from previous studies, field observations on flow regimes and professional experience validated the performance of these models. The geometric characteristics for extended floodplains and/or swamps were derived from a calibrated NASA Shuttle Radar Topographic Mission (SRTM) Digital Elevation Models (DEM) of 30 arc-seconds resolution under HEC-GeoRAS GIS extension Environment. The modelling results were considered satisfactory because the relative errors for most of applications fall below 20%. The good performance achieved is attributed to the instituted quality control measures right from suitable sites selection to hydraulic modelling phases. Modelling results confidence rating of above 3 in a scale of 1 to 5 achieved depended upon the hydraulic complexity. Based on the satisfactory results in the case studies, the authors would like to note that there are some prospects of carryingout hydraulic analysis in the regions with inadequate data. However, professional input is the key to successful modelling exercises. Therefore, follow research should use more data to verify the approach adopted.

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Ostendorf, David W., Don J. DeGroot, Wayne M. Shelburne, and Travis J. Mitchell. "Hydraulic head in a clayey sand till over multiple timescales." Canadian Geotechnical Journal 41, no. 1 (February 1, 2004): 89–105. http://dx.doi.org/10.1139/t03-074.

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This paper presents an analysis of hydraulic head data measured every 2 h for 2 years in the leading edge of a drumlin that consists of weathered, brown clayey sand till and underlying unweathered gray clayey sand till. The brown till responds as an unconfined aquifer and acts as a boundary condition for the confined gray till aquifer. Analytical models are presented for interpretation of the hydraulic head data using annual, monthly, and daily timescales, for estimation of drumlin (landform) hydraulics and till (formation) properties. The annual average head data from open-standpipe piezometers calibrate drumlin hydraulics that feature steady radial flow in the brown till, because of its higher permeability (1.1 × 1013 m2) and the finite radius of the drumlin. The lower permeability (1.4 × 1015 m2) gray till has steady cylindrical flow with an appreciable downward gradient. Open-standpipe piezometer data are modeled at the monthly timescale to confirm the landform hydraulics and calibrate a brown till macroporosity of 0.016. The amplitude of periodic monthly head fluctuations increases towards the edge of the drumlin. Hydraulic head response to aperiodic storm events is significantly magnified by this macroporosity as measured by precipitation gages and buried pressure transducers. The storm data are modeled on a daily timescale to confirm the brown till macroporosity value estimated from the monthly data and to further elucidate gray till hydraulics. Compressibility delays and attenuates the groundwater mound, with a calibrated gray till compressibility of 3 × 109 Pa1. The calibrated models accurately recover drumlin flow fields with plausible property values of the clayey sand till, and accordingly should describe other sites with similar landforms and deposits.Key words: drumlins, till, hydraulics, compressibility, permeability, macroporosity, piezometer.

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Berardi, L., and O. Giustolisi. "Calibration of Design Models for Leakage Management of Water Distribution Networks." Water Resources Management 35, no. 8 (May 26, 2021): 2537–51. http://dx.doi.org/10.1007/s11269-021-02847-x.

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AbstractWater losses in urban water distribution networks (WDN) accelerate the deterioration of such infrastructures. The enhanced hydraulic modelling provides a phenomenological representation of WDN hydraulics, including the modelling of leakages as function of pipe average pressure and deterioration. The methodological use of such models on real WDN was demonstrated to support the planning of leakage management actions. Nonetheless, many water utilities are still in the process of designing flow/pressure monitoring, thus data available are not enough to perform detailed calibration of such models.This work presents a physically based approach for the calibration of WDN hydraulic models aimed at supporting leakage management plans since early stages. The proposed procedure leverages the key role of mass balance in enhanced hydraulic models and the technical insight on pipe deterioration mechanisms for various quantity and quality of available data. Two calibration studies of real WDNs demonstrate the feasibility of the approach and show that the distribution of leakages in the WDN does not much influence the pressure values, which confirms the need for flow measurements at monitoring districts for leakage and asset management.

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Sweeney, D. G., N. J. Cromar, J. B. Nixon, C. T. Ta, and H. J. Fallowfield. "The spatial significance of water quality indicators in waste stabilization ponds - limitations of residence time distribution analysis in predicting treatment efficiency." Water Science and Technology 48, no. 2 (July 1, 2003): 211–18. http://dx.doi.org/10.2166/wst.2003.0123.

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Over the past fifty years, considerable research in waste stabilization pond operation has led to the development of a number of models used to describe the hydraulic regime and predict treatment efficiency. Models range in complexity from plug or completely mixed simplifications to computational fluid dynamics (CFD) models which are able to predict flow hydraulics at a local level. Information about the exit age of pond effluent can be used to estimate pollutant decay. However, a mechanistic approach to understanding pond operation highlights the importance of knowing both the time and spatial history of pond effluent. A CFD model of a large pond system was constructed to demonstrate various hydraulic scenarios under different boundary conditions. Two scenarios were compared to visually demonstrate the effects of differing hydraulic conditions. Typical mechanistic models were applied to each condition to quantify biological differences. This simple example indicates that integrating biological and localised flow models will lead to a more holistic understanding of pond operation and treatment efficiency.

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Marthews, T. R., C. A. Quesada, D. R. Galbraith, Y. Malhi, C. E. Mullins, M. G. Hodnett, and I. Dharssi. "High-resolution hydraulic parameter maps for surface soils in tropical South America." Geoscientific Model Development 7, no. 3 (May 6, 2014): 711–23. http://dx.doi.org/10.5194/gmd-7-711-2014.

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Abstract. Modern land surface model simulations capture soil profile water movement through the use of soil hydraulics sub-models, but good hydraulic parameterisations are often lacking, especially in the tropics. We present much-improved gridded data sets of hydraulic parameters for surface soil for the critical area of tropical South America, describing soil profile water movement across the region to 30 cm depth. Optimal hydraulic parameter values are given for the Brooks and Corey, Campbell, van Genuchten–Mualem and van Genuchten–Burdine soil hydraulic models, which are widely used hydraulic sub-models in land surface models. This has been possible through interpolating soil measurements from several sources through the SOTERLAC soil and terrain data base and using the most recent pedotransfer functions (PTFs) derived for South American soils. All soil parameter data layers are provided at 15 arcsec resolution and available for download, this being 20x higher resolution than the best comparable parameter maps available to date. Specific examples are given of the use of PTFs and the importance highlighted of using PTFs that have been locally parameterised and that are not just based on soil texture. We discuss current developments in soil hydraulic modelling and how high-resolution parameter maps such as these can improve the simulation of vegetation development and productivity in land surface models.

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Mursinna, A., Erica McCormick, Katie Van Horn, Lisa Sartin, and Ashley Matheny. "Plant Hydraulic Trait Covariation: A Global Meta-Analysis to Reduce Degrees of Freedom in Trait-Based Hydrologic Models." Forests 9, no. 8 (July 25, 2018): 446. http://dx.doi.org/10.3390/f9080446.

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Current vegetation modeling strategies use broad categorizations of plants to estimate transpiration and biomass functions. A significant source of model error stems from vegetation categorizations that are mostly taxonomical with no basis in plant hydraulic strategy and response to changing environmental conditions. Here, we compile hydraulic traits from 355 species around the world to determine trait covariations in order to represent hydraulic strategies. Simple and stepwise regression analyses demonstrate the interconnectedness of multiple vegetative hydraulic traits, specifically, traits defining hydraulic conductivity and vulnerability to embolism with wood density and isohydricity. Drought sensitivity is strongly (Adjusted R2 = 0.52, p < 0.02) predicted by a stepwise linear model combining rooting depth, wood density, and isohydricity. Drought tolerance increased with increasing wood density and anisohydric response, but with decreasing rooting depth. The unexpected response to rooting depth may be due to other tradeoffs within the hydraulic system. Rooting depth was able to be predicted from sapwood specific conductivity and the water potential at 50% loss of conductivity. Interestingly, the influences of biome or growth form do not increase the accuracy of the drought tolerance model and were able to be omitted. Multiple regression analysis revealed 3D trait spaces and tradeoff axes along which species’ hydraulic strategies can be analyzed. These numerical trait spaces can reduce the necessary input to and parameterization of plant hydraulics modules, while increasing the physical representativeness of such simulations.

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Marthews, T. R., C. A. Quesada, D. R. Galbraith, Y. Malhi, C. E. Mullins, M. G. Hodnett, and I. Dharssi. "High-resolution hydraulic parameter maps for surface soils in tropical South America." Geoscientific Model Development Discussions 6, no. 4 (December 17, 2013): 6741–74. http://dx.doi.org/10.5194/gmdd-6-6741-2013.

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Abstract. Modern land surface model simulations capture soil profile water movement through the use of soil hydraulics sub-models, but good hydraulic parameterisations are often lacking, especially in the tropics. We present much-improved gridded datasets of hydraulic parameters for surface soil for the critical area of tropical South America, describing soil profile water movement across the region to 30 cm depth. Optimal hydraulic parameter values are given for the Brooks and Corey, Campbell, van Genuchten–Mualem and van Genuchten–Burdine soil hydraulic models, which are widely-used hydraulic sub-models in Land Surface Models. This has been possible through interpolating soil measurements from several sources through the SOTERLAC soil and terrain database and using the most recent pedotransfer functions (PTFs) derived for South American soils. All soil parameter data layers are provided at 15 arcsec resolution and available for download, this being 20 × higher resolution than the best comparable parameter maps available to date. Specific examples are given of the use of PTFs and the importance highlighted of using PTFs that have been locally-parameterised and that are not just based on soil texture. Details are provided specifically on how to assemble the ancillary data files required for grid-based vegetation simulation using the Joint UK Land Environment Simulator (JULES). We discuss current developments in soil hydraulic modelling and how high-resolution parameter maps such as these can improve the simulation of vegetation development and productivity in land surface models.

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Marengo, Humberto, Álvaro A. Aldama, and Ignacio Romero. "Un nuevo criterio para la estimación de rugosidad compuesta en modelos hidráulicos." Tecnología y ciencias del agua 11, no. 5 (September 1, 2020): 171–224. http://dx.doi.org/10.24850/j-tyca-2020-05-05.

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Rajaratnam, N., C. Katopodis, and R. Paccagnan. "Field studies of fishways in Alberta." Canadian Journal of Civil Engineering 19, no. 4 (August 1, 1992): 627–38. http://dx.doi.org/10.1139/l92-072.

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This paper presents a detailed account of field studies performed on one pool-weir and several Denil and vertical slot fishways in the province of Alberta. The pictures show the broad features of the flow. The velocity profiles obtained in the field studies have confirmed the measurements made in the laboratory on scale models and have enhanced the general picture, particularly for the vertical slot fishways. This paper provides hydraulic engineers with information for understanding the primary hydraulic characteristics of fishways. Key words: fishways, field studies, hydraulics, open-channel flow, turbulent flow.

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Mischuk, Dmitry. "HYDRAULIC CYLINDER OF THE VOLUMETRIC HYDRAULIC DRIVE RESEARCH OF THE DYNAMIC MODEL." Gіrnichі, budіvelnі, dorozhnі ta melіorativnі mashini, no. 87 (July 8, 2016): 74–81. http://dx.doi.org/10.26884/damu.a168713.

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Parekh, Siddharth, Ali Pilehvari, and Robert Serth. "Prediction of Fluid Behavior Using Generalized Hydraulic Calculation Method in Hydraulic Fractures." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 81, no. 1 (March 5, 2021): 120–30. http://dx.doi.org/10.37934/arfmts.81.1.120130.

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Hydraulic fracturing has been used as one of the stimulation techniques to economically increase oil and gas production by creating small cracks in subsurface geologic formations to allow oil or gas to move toward a producing well. Hydraulics plays a vital role in many oil field operations including drilling, completion, fracturing and production. In the case of fracturing, however, the role of hydraulics becomes important since optimized hydraulics can minimize the cost and conversely, any miscalculations may cause problems such as the fluid loss or may potentially even lead to loss of the well. The current methods of the hydraulic calculation for non-Newtonian fluids necessitate determination of the robust model. This paper presented a new method for calculating pressure losses in the hydraulic fractures. The objective of this study was to develop the generalized model for hydraulic calculation for non-Newtonian fluid and run the case studies for the model validation. In the present work, detailed algorithm for the hydraulic calculation has been developed and then programmed in C++. The only input to the program is the raw rheological data, shear stress versus shear rate and the geometrical characteristics of the slit. Model validation with the new method has established a very small percentage difference between the values predicted by the model and experimental data. The results demonstrate that the new method is accurately predicting the pressure drop in both laminar and turbulent flow regimes. It is shown that the fluid behavior is more accurately represented using the new method than that with the standard fluid models available in the petroleum industry. Further validation and development to be carried out using experimental data for variety of fluid types.

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Carleton, Tyler J., and Steven R. Fassnacht. "Linking Hydrologic and Hydraulic Data with Models to Assess Flow and Channel Alteration at Hog Park, Wyoming USA." Hydrology 7, no. 2 (May 23, 2020): 29. http://dx.doi.org/10.3390/hydrology7020029.

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Transbasin diversions and dams allow for water uses when and where there is high demand and low supply, but can come with an expense to the environment. This paper presents a linkage of hydrologic and hydraulic modeling and datasets to assess the hydrologic and hydraulic stability within a transbasin watershed as an approach for meeting water use targets and safeguarding environmental sustainability. The approach used a Prediction in Ungauged Basin (PUB) regionalization technique that completed the parameterization of a study watershed hydrologic model by transferring calibrated parameters from a reference watershed hydrologic model. This resulted in a long-term, simulated natural flow record that was compared to the measured modified flow record for the same time period to assess flow alteration. In the sensitive reach, hydraulic modeling results tracked channel response from before hydrologic modification to baseline using repeated survey years during the hydrologic modification. The combined assessment of hydrology and hydraulics highlighted the relation between flow regime and channel form.

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Perrin, O., S. Christophe, F. Jacquinod, and O. Payrastre. "VISUAL ANALYSIS OF INCONSISTENCIES IN HYDRAULIC SIMULATION DATA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B4-2020 (August 25, 2020): 795–801. http://dx.doi.org/10.5194/isprs-archives-xliii-b4-2020-795-2020.

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Abstract. We present our contribution to the geovisualization and visual analysis of hydraulic simulation data, based on an interdisciplinary research work undertaken by researchers in geographic information sciences and in hydraulics. The positive feedback loop between researchers favored the proposal of visualization tools enabling visual reasoning on hydraulic simulated data so as to infer knowledge on the simulation model. We interactively explore and design 2D multi-scale styles to render hydraulic simulated data, in order to support the identification over large simulation domains of possible local inconsistencies related to input simulation data, simulation parameters or simulation workflow. Models have been implemented into QGIS and are reusable for other input data and territories.

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Baird, Drew, Benjamin Abban, S. Scurlock, Steven Abt, and Christopher Thornton. "Two-Dimensional Numerical Modeling of Flow in Physical Models of Rock Vane and Bendway Weir Configurations." Water 13, no. 4 (February 10, 2021): 458. http://dx.doi.org/10.3390/w13040458.

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While there are a wide range of design recommendations for using rock vanes and bendway weirs as streambank protection measures, no comprehensive, standard approach is currently available for design engineers to evaluate their hydraulic performance before construction. This study investigates using 2D numerical modeling as an option for predicting the hydraulic performance of rock vane and bendway weir structure designs for streambank protection. We used the Sedimentation and River Hydraulics (SRH)-2D depth-averaged numerical model to simulate flows around rock vane and bendway weir installations that were previously examined as part of a physical model study and that had water surface elevation and velocity observations. Overall, SRH-2D predicted the same general flow patterns as the physical model, but over- and underpredicted the flow velocity in some areas. These over- and underpredictions could be primarily attributed to the assumption of negligible vertical velocities. Nonetheless, the point differences between the predicted and observed velocities generally ranged from 15 to 25%, with some exceptions. The results showed that 2D numerical models could provide adequate insight into the hydraulic performance of rock vanes and bendway weirs. Accordingly, design guidance and implications of the study results are presented for design engineers.

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Matus, Sean A., Francina Dominguez, Daniel R. Gambill, and Heidi R. Howard. "Embracing Uncertainty: Using Probabilistic Weather Forecasts to Make Ensemble Hydraulic Predictions at Remote Low-Water Crossings." Journal of Hydrometeorology 21, no. 5 (May 2020): 953–69. http://dx.doi.org/10.1175/jhm-d-19-0238.1.

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AbstractLow-water crossings are structures designed to be overtopped during high river flows. These structures are usually constructed in remote locations, making timely emergency response difficult in case of flooding. In this work, five historical flooding events were hindcasted at a remote low-water crossing in central Texas. An ensemble of model-simulated precipitation forcing cascades uncertainty through hydrologic and hydraulic models. Each precipitation ensemble member corresponds to an independent model run, resulting in an ensemble 24-h streamflow forecast initialized at 0000 UTC. In addition to the hydrologic conditions, the forecast is expanded to predict river hydraulics, through flow velocity and depth. Analysis of the five hindcast events indicates that cascading probabilistic precipitation through hydrologic and hydraulic models adds robustness to river forecasts compared to deterministic methods. The approach provides a means to communicate the uncertainty of predictions through the ensemble spread. Analysis of deterministic hazard thresholds suggest that a hydraulic stability threshold, calculated as the multiplication of flow velocity and depth, is a useful alternative approach to NWS high-water categories for communicating hydrologic/hydraulic risk, as well as associated model uncertainty in the simplest manner possible.

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Power, Mary E., Adrian Sun, Gary Parker, William E. Dietrich, and J. Timothy Wootton. "Hydraulic Food-Chain Models." BioScience 45, no. 3 (March 1995): 159–67. http://dx.doi.org/10.2307/1312555.

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Ormsbee, Lindell E., and Srinivasa Lingireddy. "Calibrating hydraulic network models." Journal - American Water Works Association 89, no. 2 (February 1997): 42–50. http://dx.doi.org/10.1002/j.1551-8833.1997.tb08177.x.

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Randle, Timothy J. "Use of Multidimensional Models to Investigate Boundary Shear Stress through Meandering River Channels." Water 12, no. 12 (December 13, 2020): 3506. http://dx.doi.org/10.3390/w12123506.

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Three-dimensional hydraulics were simulated through a wide range of synthetically generated meandering river channels to determine how channel curvature and width would correlate with the maximum boundary shear stress. Multidimensional models were applied, similar to a computational flume to simulate a wide range of 72 meandering channels, developed from sine-generated curves. Cannel sinuosity ranged from 1.1 to 3.0 and included five consecutive meander bends. Longitudinal slopes of the various channels spanned four orders of magnitude, while bankfull discharges spanned three orders of magnitude. Using results from one-half of the simulation sets, an empirical correlation was found to predict the maximum boundary shear stress as a function of dimensionless ratios of channel curvature and width. The remaining simulation sets were used for verification. Multidimensional models were used to simulate channel hydraulics to efficiently investigate a wide range of channel sinuosity, width/depth ratios, bankfull discharges, and valley slopes. When simulating such a wide range of channel conditions, multidimensional models offer a more efficiency method of generating consistent datasets than either field studies or physical modeling. This paper demonstrates how multidimensional models can be used to identify important hydraulic relationships that are otherwise difficult to determine.

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Martins, Ricardo, Jorge Leandro, and Rita Fernandes de Carvalho. "Characterization of the hydraulic performance of a gully under drainage conditions." Water Science and Technology 69, no. 12 (March 31, 2014): 2423–30. http://dx.doi.org/10.2166/wst.2014.168.

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During rainfall events with low return periods (1–20 years) the drainage system can provide some degree of protection to urban areas. The system design is based not only on good hydraulic performance of the surface and the sewer network but also on their linking elements. Although the linking elements are of utmost importance as they allow the exchange of flow between the surface and the sewer network, there is a lack of studies that thoroughly characterize them. One crucial structural part of those elements is the gully. State-of-the-art dual-drainage models often use simplified formulae to replicate the gully hydraulic behaviour that lacks proper validation. This work focuses on simulating, both numerically and experimentally, the hydraulic performance of a 0.6 × 0.3 × 0.3 [m] (L × W × D) gully located inside an 8 × 0.5 × 0.5 [m] rectangular channel. The numerical simulations are conducted with the OpenFOAM toolbox and validated with water level measurements in the Multiple-Linking-Element experimental installation located at the Laboratory of Hydraulics of the University of Coimbra. The results provide a complete three-dimensional insight of the hydraulic behaviour of the flow inside the gully, and discharge coefficient formulae are disclosed that can be directly applied in dual-drainage models as internal boundary conditions.

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Avramova, M., A. Velazquez-Lozada, and A. Rubin. "Comparative Analysis of CTF and Trace Thermal-Hydraulic Codes Using OECD/NRC PSBT Benchmark Void Distribution Database." Science and Technology of Nuclear Installations 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/725687.

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The international OECD/NRC PSBT benchmark has been established to provide a test bed for assessing the capabilities of thermal-hydraulic codes and to encourage advancement in the analysis of fluid flow in rod bundles. The benchmark was based on one of the most valuable databases identified for the thermal-hydraulics modeling developed by NUPEC, Japan. The database includes void fraction and departure from nucleate boiling measurements in a representative PWR fuel assembly. On behalf of the benchmark team, PSU in collaboration with US NRC has performed supporting calculations using the PSU in-house advanced thermal-hydraulic subchannel code CTF and the US NRC system code TRACE. CTF is a version of COBRA-TF whose models have been continuously improved and validated by the RDFMG group at PSU. TRACE is a reactor systems code developed by US NRC to analyze transient and steady-state thermal-hydraulic behavior in LWRs and it has been designed to perform best-estimate analyses of LOCA, operational transients, and other accident scenarios in PWRs and BWRs. The paper presents CTF and TRACE models for the PSBT void distribution exercises. Code-to-code and code-to-data comparisons are provided along with a discussion of the void generation and void distribution models available in the two codes.

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Loi, Nguyen Kim, Nguyen Duy Liem, Le Hoang Tu, Nguyen Thi Hong, Cao Duy Truong, Vo Ngoc Quynh Tram, Tran Thong Nhat, Tran Ngoc Anh, and Jaehak Jeong. "Automated procedure of real-time flood forecasting in Vu Gia – Thu Bon river basin, Vietnam by integrating SWAT and HEC-RAS models." Journal of Water and Climate Change 10, no. 3 (August 24, 2018): 535–45. http://dx.doi.org/10.2166/wcc.2018.015.

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Abstract The precise and reliable simulation of hydrologic and hydraulic processes is important for efficient flood forecasting and warning. The study proposes a real-time flood forecasting system which integrates a coupled hydrological-hydraulic modeling system, weather station network, and stream gauges in a web-based visualization environment. An automated procedure was developed for linking dynamically terrestrial rainfall-runoff processes and river hydraulics by coupling the SWAT hydrological model and the HEC-RAS hydraulic model. The flood forecasting system was trialed in the Vu Gia – Thu Bon river basin, Quang Nam province, Vietnam. The results showed good statistical correlation between predicted and measured stream flow for a 10-year calibration period (R² = 0.95, NSI = 0.95, PBIAS = −1.54) and during the following 10-year validation period as well (R² = 0.93, NSI = 0.93, PBIAS = 6.18). A close-up analysis of individual storm events indicated that the magnitude and timing of peak floods were accurately predicted in 2015 (R² = 0.88, NSI = 0.69, PBIAS = 4.50) and 2016 (R² = 0.80, NSI = 0.93, PBIAS = 6.18). In addition, the automated procedure was demonstrated to be reliable with dependable computational efficiency of less than 5 minutes' processing time.

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Garcia, Matthew, Andrew Juan, and Philip Bedient. "Integrating Reservoir Operations and Flood Modeling with HEC-RAS 2D." Water 12, no. 8 (August 12, 2020): 2259. http://dx.doi.org/10.3390/w12082259.

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Current free to use models developed by the United States Army Corps of Engineers (USACE) perform unique functions (e.g., hydrology, hydraulics, reservoir operations, and flood impact analysis) that are widely used in numerous studies and applications. These models are commonly set up in a framework that is limited to point source connections, which is problematic in regions with flat topography and complex hydrodynamics. The separate models need to be integrally linked and jointly considered for accurate risk communication and decision-making, especially during major storm events. Recently, Hurricane Harvey (2017) exposed the shortcomings of the existing framework in West Harris County, TX, where an insufficient understanding of potential flood risk and impacts contributed to the extensive flood damages sustained in the region. This work illustrates the possibility of using a single hydraulic model, HEC-RAS 2D, to perform all hydrologic, hydraulic, and reservoir operations modeling necessary for accurate flood impact assessments. Implications of this study include a simplification of the entire flood impact analysis, which could help future flood risk communication and emergency planning.

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Bolea, Yolanda, Vicenç Puig, and Antoni Grau. "Discussion on Muskingum versus Integrator-Delay Models for Control Objectives." Journal of Applied Mathematics 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/197907.

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A comparative study about two models, Muskingum and integrator-delay (ID) models, for canal control is presented. The former is a simplified hydrological model which is very simple and extensively used in hydraulic engineering for simulation and prediction. The latter is also a model with physical meaning and is widely used for irrigation canals control. Due to a lack of general awareness of Muskingum prediction model in regulation from the control community, authors present this comparative study with the ID control model. Both models have been studied and analyzed for control purposes. This study has been carried out and validated in a real irrigation canal, at Aghili irrigation district in Iran, using two traditional control approaches, PID with feedback and predictive control. The results demonstrate the advantages and drawbacks of both models, showing the benefits and limitations of using the widespread Muskingum model among the hydraulics scientific community for control design.

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Nguyen, Thuy Huu, Matthias Langensiepen, Jan Vanderborght, Hubert Hüging, Cho Miltin Mboh, and Frank Ewert. "Comparison of root water uptake models in simulating CO<sub>2</sub> and H<sub>2</sub>O fluxes and growth of wheat." Hydrology and Earth System Sciences 24, no. 10 (October 23, 2020): 4943–69. http://dx.doi.org/10.5194/hess-24-4943-2020.

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Abstract. Stomatal regulation and whole plant hydraulic signaling affect water fluxes and stress in plants. Land surface models and crop models use a coupled photosynthesis–stomatal conductance modeling approach. Those models estimate the effect of soil water stress on stomatal conductance directly from soil water content or soil hydraulic potential without explicit representation of hydraulic signals between the soil and stomata. In order to explicitly represent stomatal regulation by soil water status as a function of the hydraulic signal and its relation to the whole plant hydraulic conductance, we coupled the crop model LINTULCC2 and the root growth model SLIMROOT with Couvreur's root water uptake model (RWU) and the HILLFLOW soil water balance model. Since plant hydraulic conductance depends on the plant development, this model coupling represents a two-way coupling between growth and plant hydraulics. To evaluate the advantage of considering plant hydraulic conductance and hydraulic signaling, we compared the performance of this newly coupled model with another commonly used approach that relates root water uptake and plant stress directly to the root zone water hydraulic potential (HILLFLOW with Feddes' RWU model). Simulations were compared with gas flux measurements and crop growth data from a wheat crop grown under three water supply regimes (sheltered, rainfed, and irrigated) and two soil types (stony and silty) in western Germany in 2016. The two models showed a relatively similar performance in the simulation of dry matter, leaf area index (LAI), root growth, RWU, gross assimilation rate, and soil water content. The Feddes model predicts more stress and less growth in the silty soil than in the stony soil, which is opposite to the observed growth. The Couvreur model better represents the difference in growth between the two soils and the different treatments. The newly coupled model (HILLFLOW–Couvreur's RWU–SLIMROOT–LINTULCC2) was also able to simulate the dynamics and magnitude of whole plant hydraulic conductance over the growing season. This demonstrates the importance of two-way feedbacks between growth and root water uptake for predicting the crop response to different soil water conditions in different soils. Our results suggest that a better representation of the effects of soil characteristics on root growth is needed for reliable estimations of root hydraulic conductance and gas fluxes, particularly in heterogeneous fields. The newly coupled soil–plant model marks a promising approach but requires further testing for other scenarios regarding crops, soil, and climate.

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Bayon-Barrachina, Arnau, and Petra Amparo Lopez-Jimenez. "Numerical analysis of hydraulic jumps using OpenFOAM." Journal of Hydroinformatics 17, no. 4 (March 13, 2015): 662–78. http://dx.doi.org/10.2166/hydro.2015.041.

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The present paper deals with a hydraulic jump study, characterization and numerical modeling. Hydraulic jumps constitute a common phenomenon in the hydraulics of open channels that increases the shear stress on streambeds, so promoting their erosion. A three-dimensional computational fluid dynamics model is proposed to analyze hydraulic jumps in horizontal smooth rectangular prismatic open-air channels (i.e., the so-called classical hydraulic jump). Turbulence is modeled using three widely used Reynolds-averaged Navier–Stokes (RANS) models, namely: Standard k − ɛ, RNG k − ɛ, and SST k − ω. The coexistence of two fluids and the definition of an interface between them are treated using a volume method in Cartesian grids of several element sizes. An innovative way to deal with the outlet boundary condition that allows the size of the simulated domain to be reduced is presented. A case study is conducted for validation purposes (FR1 ∼ 6.10, Re1 ∼ 3.5·105): several variables of interest are computed (sequent depths, efficiency, roller length, free surface profile, etc.) and compared to previous studies, achieving accuracies above 98% in all cases. In the light of the results, the model can be applied to real-life cases of design of hydraulic structures.

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Yakirevich, Alexander. "Water Flow, Solute and Heat Transfer in Groundwater." Water 12, no. 7 (June 28, 2020): 1851. http://dx.doi.org/10.3390/w12071851.

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Groundwater is an essential and vital water resource for drinking water production, agricultural irrigation, and industrial processes. The better understanding of physical and chemical processes in aquifers enables more reliable decisions and reduces the investments concerning water management. This Special Issue on “Water Flow, Solute and Heat Transfer in Groundwater” of Water focuses on the recent advances in groundwater dynamics. In this editorial, we introduce 12 high-quality papers that cover a wide range of issues on different aspects related to groundwater: protection from contamination, recharge, heat transfer, hydraulic parameters estimation, well hydraulics, microbial community, colloid transport, and mathematical models. By presenting this integrative volume, we aim to transfer knowledge to hydrologists, hydraulic engineers, and water resources planners who are engaged in the sustainable development of groundwater resources.

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Liu, Yanlan, Nataniel M. Holtzman, and Alexandra G. Konings. "Global ecosystem-scale plant hydraulic traits retrieved using model–data fusion." Hydrology and Earth System Sciences 25, no. 5 (May 10, 2021): 2399–417. http://dx.doi.org/10.5194/hess-25-2399-2021.

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Abstract. Droughts are expected to become more frequent and severe under climate change, increasing the need for accurate predictions of plant drought response. This response varies substantially, depending on plant properties that regulate water transport and storage within plants, i.e., plant hydraulic traits. It is, therefore, crucial to map plant hydraulic traits at a large scale to better assess drought impacts. Improved understanding of global variations in plant hydraulic traits is also needed for parameterizing the latest generation of land surface models, many of which explicitly simulate plant hydraulic processes for the first time. Here, we use a model–data fusion approach to evaluate the spatial pattern of plant hydraulic traits across the globe. This approach integrates a plant hydraulic model with data sets derived from microwave remote sensing that inform ecosystem-scale plant water regulation. In particular, we use both surface soil moisture and vegetation optical depth (VOD) derived from the X-band Japan Aerospace Exploration Agency (JAXA) Advanced Microwave Scanning Radiometer for Earth Observing System (EOS; collectively AMSR-E). VOD is proportional to vegetation water content and, therefore, closely related to leaf water potential. In addition, evapotranspiration (ET) from the Atmosphere–Land Exchange Inverse (ALEXI) model is also used as a constraint to derive plant hydraulic traits. The derived traits are compared to independent data sources based on ground measurements. Using the K-means clustering method, we build six hydraulic functional types (HFTs) with distinct trait combinations – mathematically tractable alternatives to the common approach of assigning plant hydraulic values based on plant functional types. Using traits averaged by HFTs rather than by plant functional types (PFTs) improves VOD and ET estimation accuracies in the majority of areas across the globe. The use of HFTs and/or plant hydraulic traits derived from model–data fusion in this study will contribute to improved parameterization of plant hydraulics in large-scale models and the prediction of ecosystem drought response.

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Khusainov, A. T., and A. V. Strekalov. "MODELS HYDRAULIC COMPONENTS PRODUCTIVE FORMATIONS." Oil and Gas Business, no. 5 (October 2014): 119–33. http://dx.doi.org/10.17122/ogbus-2014-5-119-133.

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Hall, Jim W., Shawn A. Boyce, Yueling Wang, Richard J. Dawson, Stefano Tarantola, and Andrea Saltelli. "Sensitivity Analysis for Hydraulic Models." Journal of Hydraulic Engineering 135, no. 11 (November 2009): 959–69. http://dx.doi.org/10.1061/(asce)hy.1943-7900.0000098.

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Zimoch, Izabela, and Ewelina Bartkiewicz. "Process of hydraulic models calibration." E3S Web of Conferences 59 (2018): 00007. http://dx.doi.org/10.1051/e3sconf/20185900007.

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Mathematical modelling of the water supply systems (WSS) and water quality changes in the system is a complex and difficult task to solve, it requires an interdisciplinary approach to considering the determinants of WSS work. Prognosis models of the WSS in relation to hydraulic quantities are well known and there are many packages that implement these models. These packages allow you to calculate the flow and pressure in the water distribution system under certain operating conditions. However, to make a hydraulic model a useful tool in the management of water supply systems, a calibration process is required. This process involves estimating model parameters to minimize the difference between model results and actual observations. This is a complex and multi-stage process where the network graph and parameters such as roughness coefficient, pump characteristics, or nodal demands are checked and corrected. The following work contains a complex process of calibration of the actual WSS that supplies water to the customers of the selected part of the Silesian agglomeration.

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Gaines, Roger A., and Stephen T. Maynord. "Microscale Loose-Bed Hydraulic Models." Journal of Hydraulic Engineering 127, no. 5 (May 2001): 335–38. http://dx.doi.org/10.1061/(asce)0733-9429(2001)127:5(335).

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Ramos, Helena M., Armando Carravetta, Aonghus Mc Nabola, and Kemi Adeyeye. "Environmental Hydraulics Research." Water 12, no. 10 (October 1, 2020): 2749. http://dx.doi.org/10.3390/w12102749.

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Environmental hydraulics research includes the different domains of hydrodynamics, such as the investigation and implementation of the physical and experimental applications, and research into the quantity, quality, modelling and simulation of the attributes associated with flowing water. This topic is studied both from a technical and environmental point of view, with the objective of protecting and enhancing the quality of the environment. It is a cross-disciplinary field of study which comprises open channel/river flows and pressurised systems, combining, among others, new technological, social, and environmental hydraulic challenges. It provides researchers and engineers working in water-related fields with available information, new concepts and tools, new design solutions, eco-friendly technologies, and the advanced materials necessary to address the increasing challenges of ensuring a sustainable water environment—that is, a water environment effectively managed and adequated for generations to come by promoting the adaptation, flexibility, integration and sustainability of recognised environmental solutions. Using advanced numerical and physical models in field experiments, and tests in different types of laboratory set-ups, specialists in environmental hydraulics produce the best analyses, concepts, techniques, tools, and solutions to environmental hydraulic problems, as well as in relation to the water, energy and environmental nexus.

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Lohrasbi, Alireza, Moharram Dolatshahi Pirooz, and Alireza Lavaei. "Hydraulic Model of Dam Break Using Navier Stokes Equation with Arbitrary Lagrangian-Eulerian Approach." International Journal of Engineering and Technology 8, no. 4 (April 2016): 249–53. http://dx.doi.org/10.7763/ijet.2016.v6.893.

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Lohrasbi, Alireza, Moharram Dolatshahi Pirooz, and Alireza Lavaei. "Hydraulic Model of Dam Break Using Navier Stokes Equation with Arbitrary Lagrangian-Eulerian Approach." International Journal of Engineering and Technology 8, no. 4 (April 2016): 249–53. http://dx.doi.org/10.7763/ijet.2016.v8.893.

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Izumi, Tomoki, Junichiro Takeuchi, Toshihiko Kawachi, Koichi Unami, and Shigeya Maeda. "An Inverse Method to Estimate Soil Hydraulic Properties in Saturated-unsaturated Groundwater Flow Model." Journal of Rainwater Catchment Systems 13, no. 2 (2008): 23–28. http://dx.doi.org/10.7132/jrcsa.kj00004871197.

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Lamouroux, Nicolas, and Ian G. Jowett. "Generalized instream habitat models." Canadian Journal of Fisheries and Aquatic Sciences 62, no. 1 (January 1, 2005): 7–14. http://dx.doi.org/10.1139/f04-163.

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Conventional instream habitat models (e.g., the physical habitat simulation system) predict the impact of regulation on the habitats of freshwater taxa. They link a hydraulic model with microhabitat-suitability models for taxa to predict habitat values at various discharge rates. Their use requires considerable field effort and experience. Recent analyses performed in France suggested that comparable results could be achieved using simplified hydraulic data. We tested this approach for 99 stream reaches and nine aquatic taxa in New Zealand. The resulting generalized habitat models predict habitat values similar to those predicted by conventional models from simplified hydraulic data (depthdischarge and widthdischarge relationships, average particle size, and mean annual discharge). As in France, within-reach changes in habitat values were linked to the specific discharge of reaches, while between-reach changes depended mainly on the Froude number at mean annual discharge. The generalized models perform well outside their calibration range. Models previously developed in France perform well in New Zealand. Such generalized models contribute to identifying the key hydraulic variables for freshwater taxa and should facilitate habitat studies worldwide.

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Zhang, Fei, Shicheng Zhang, Weizhang Huang, and Xianping Li. "A Study on Moving Mesh Finite Element Solution of Phase-Field Models for Hydraulic Fracturing." International Journal of Chemical Engineering and Applications 9, no. 2 (April 2018): 51–57. http://dx.doi.org/10.18178/ijcea.2018.9.2.698.

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D’Auria, Francesco, and Giorgio Galassi. "The Best Estimate Plus Uncertainty approach in nuclear reactor safety and licensing: Brief history and the elements after licensing." Nuclear Technology and Radiation Protection 34, no. 3 (2019): 299–312. http://dx.doi.org/10.2298/ntrp190413022d.

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The best estimate plus uncertainty is, at the same time, an approach, a procedure and a frame- work in nuclear thermal-hydraulics and nuclear reactor safety and licensing. The motivation at the basis of the best estimate plus uncertainty is the lack of knowledge in the areas of single and, mainly, two-phase transient thermal-hydraulics. In other terms and introducing some simplifications, the insufficient knowledge of turbulence imposes the design of roadmaps for the application of imperfect (thermal-hydraulic) models to the evaluation of design features and of safety for complex technological installations or systems like the nuclear power plants and, more specifically, the water cooled nuclear reactors. Furthermore, the legal counterpart of nuclear reactor safety, or the licensing, is concerned: therefore the best estimate plus uncertainty must account for rules and regulations derived from the fundamental radioprotection principle which imposes the minimization of the impact of radiations upon humans and the environment under any circumstance. In the present paper, the key elements of the approach are identified and characterized. These shall be seen as the support for a consistent application of thermal-hydraulics to the design and safety of water-cooled nuclear reactors.

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Aguilar, José V., Pedro Langarita, Lorenzo Linares, Manuel Gómez, and José Rodellar. "An adaptive predictive approach for river level forecasting." Journal of Hydroinformatics 15, no. 2 (December 19, 2012): 232–45. http://dx.doi.org/10.2166/hydro.2012.172.

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Efficient flood management requires accurate real-time forecasts to allow early warnings, real-time control of hydraulics structures, or other actions. Commercially available computing tools typically use hydraulic models derived from the numerical approximation of Saint-Venant equations. These tools need powerful computers, accurate knowledge of the riverbed topography, and skilled operators with a not insignificant hydraulic background. This paper presents an alternative approach in which the river basin is modeled as a network of cascade interconnected input–output systems. Each system is modeled by an adaptive predictive expert model, which provides real-time fast and accurate forecasts over a moving prediction horizon. The approach is evaluated using real data from the Ebro river basin in Spain. The main concluded advantages of the new approach are: (1) the formulation is simple with low computational burden; (2) it does not require topographic information on the river waterbeds; (3) the forecast may be performed autonomously.

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Jaeger, Wadim, Wolfgang Hering, Martin Lux, and Fabien Portes. "ICONE23-1101 LIQUID METAL THERMAL HYDRAULICS IN RECTANGULAR DUCTS : REVIEW, PROPOSAL AND VALIDATION OF EMPIRICAL MODELS." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2015.23 (2015): _ICONE23–1—_ICONE23–1. http://dx.doi.org/10.1299/jsmeicone.2015.23._icone23-1_56.

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Jocea, Andreea Florina, E. G. Crăciun, and A. Anton. "Approximation Of Scours Using Terrestrial 3D Laser Scanning." Journal of Applied Engineering Sciences 5, no. 1 (May 1, 2015): 31–36. http://dx.doi.org/10.1515/jaes-2015-0004.

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Abstract In designing artwork as bridges, hydraulic calculations have a very important role due to the fact that they are behind their sizing. Bridge designer must therefore possess knowledge of hydrology, hydraulics of bridges and river banks regularization. A problem that arises during the design stage of bridges is the scour phenomenon surrounding bridge pier. Over time, there have been conducted a number of studies which led to the provision of a plurality of mathematical models that are intended scour prediction. In the present article we will present an experimental study to determine the bed profile and measurement of scours products around a pier bridge using 3D terrestrial laser scanner.

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Meirmanov, Anvarbek, and Irina Nekrasova. "Mathematical models of a hydraulic shock." Journal of Mathematical Analysis and Applications 408, no. 1 (December 2013): 76–90. http://dx.doi.org/10.1016/j.jmaa.2013.05.024.

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ten Brummelhuis, P. G. J. "Parameter Estimation in Stochastic Hydraulic Models." IFAC Proceedings Volumes 22, no. 4 (June 1989): 135–40. http://dx.doi.org/10.1016/s1474-6670(17)53532-6.

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Zhao, Hongbo, Zhen Li, Changxing Zhu, and Zhongliang Ru. "Reliability analysis models for hydraulic fracturing." Journal of Petroleum Science and Engineering 162 (March 2018): 150–57. http://dx.doi.org/10.1016/j.petrol.2017.12.048.

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Leopardi, Maurizio. "On roughness similarity of hydraulic models." Journal of Hydraulic Research 42, no. 3 (January 2004): 239–45. http://dx.doi.org/10.1080/00221686.2004.9728389.

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Gorodilov, L. V. "Mathematical Models of Hydraulic Percussion Systems." Journal of Mining Science 41, no. 5 (September 2005): 475–89. http://dx.doi.org/10.1007/s10913-006-0010-2.

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Journal articles on the topic 'Hydraulisk modell'

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