Preprints
Filtering by Subject: Hydraulic Engineering
External control and automatic calibration of the HEC-RAS NSM-I water quality model
Published: 2020-03-22
Subjects: Civil and Environmental Engineering, Engineering, Environmental Engineering, Hydraulic Engineering
Calibration of models is a common procedure required to properly reproduce a system under analysis. In the present study, we developed a tool integrating the HEC-RAS NSM-I water quality model with the optimization algorithm SCE-UA in order to allow the automatic calibration. The tool’s performance was assessed in two experiments involving a theoretical situation, when it was used to approximate a [...]
On the potential of linked-basin tidal power plants: an operational and coastal modelling assessment
Published: 2020-02-03
Subjects: Civil and Environmental Engineering, Computational Engineering, Engineering, Environmental Engineering, Hydraulic Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Single-basin tidal range power plants have the advantage of predictable energy outputs, but feature non-generation periods in every tidal cycle. Linked-basin tidal power systems can reduce this variability and consistently generate power. However, as a concept the latter are under-studied with limited information on their performance relative to single-basin designs. In addressing this, we [...]
A web application for hydrogeomorphic flood hazard mapping
Published: 2020-01-09
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Hydraulic Engineering, Hydrology, Physical Sciences and Mathematics
A detailed delineation of flood-prone areas over large regions represents a challenge that cannot be easily solved with today’s resources. The main limitations lie in algorithms and hardware, but also costs, scarcity and sparsity of data and our incomplete knowledge of how inundation events occur in different river floodplains. We showcase the implementation of a data-driven web application for [...]
Information-theoretic Portfolio Decision Model for Optimal Flood Management
Published: 2019-06-27
Subjects: Civil and Environmental Engineering, Civil Engineering, Computational Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Health and Protection, Environmental Sciences, Geomorphology, Hydraulic Engineering, Hydrology, Life Sciences, Natural Resources and Conservation, Natural Resources Management and Policy, Operations Research, Systems Engineering and Industrial Engineering, Other Civil and Environmental Engineering, Other Engineering, Other Environmental Sciences, Other Physical Sciences and Mathematics, Physical Sciences and Mathematics, Probability, Risk Analysis, Statistics and Probability, Sustainability, Systems Engineering, Water Resource Management
The increasing impact of flooding urges more effective flood management strategies to guarantee sustainable ecosystem development. Recent catastrophes underline the importance of avoiding local flood management, but characterizing large scale basin wide approaches for systemic flood risk management. Here we introduce an information-theoretic Portfolio Decision Model (iPDM) for the optimization of [...]
Global resource potential of seasonal pumped-storage
Published: 2019-06-21
Subjects: Civil and Environmental Engineering, Engineering, Geotechnical Engineering, Hydraulic Engineering
The risk of seasonal mismatches between electricity supply and demand is increasing due to expanded use of wind, solar and hydropower resources. Power system planners are thus in search of low-cost seasonal energy storage options. Seasonal Pumped-Storage (SPS) can provide short, medium and long-term energy storage at a relatively low-cost and provides co-benefits in the form of freshwater storage [...]
Analysis of Persistence in the Flood Timing and the Role of Catchment Wetness on Flood Generation in a Large River Basin in India
Published: 2019-05-08
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Hydraulic Engineering, Hydrology, Physical Sciences and Mathematics, Statistics and Probability
This study contributes to the understanding of the timing of occurrence of floods and role of the catchment wetness in flood processes (i.e., magnitude and the timing of floods) over one of the largest tropical pluvial river basin system, Mahanadi, in India. Being located in the monsoon ‘core’ region (18° - 28° N latitude and 73° - 82° E longitude) and its proximity to Bay of Bengal, Mahanadi [...]
Are Detected Trends in Flood Magnitude and Shifts in the Timing of Floods of A Major River Basin in India, Linked To Anthropogenic Stressors?
Published: 2019-04-10
Subjects: Applied Statistics, Civil and Environmental Engineering, Earth Sciences, Engineering, Hydraulic Engineering, Hydrology, Mathematics, Physical Sciences and Mathematics, Statistics and Probability
Analyzing of trends in flood magnitude and the timing of the dates of flood occurrences of large river basins across the globe are essential for understanding changes in water availability (high or low flows) and assessing the fidelity of global hydrological models. Our research is motivated by the recent six major consecutive floods in Mahanadi (years: 2001, 2003, 2006, 2008, 2011 and 2013) [...]
Hydrodynamic control of gas-exchange velocity in small streams
Published: 2019-03-02
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Fluid Dynamics, Hydraulic Engineering, Physical Sciences and Mathematics, Physics, Planetary Sciences
Gas exchange is a critical component of any biogeochemical mass balance model of dissolved gases in aquatic systems, yet the magnitude and drivers of spatial and temporal variations of air-water exchange rates in shallow streams are poorly understood. We investigated the relationships between gas exchange velocity of carbon dioxide and methane and flow hydraulics at different sections along a [...]
Utilising the flexible generation potential of tidal range power plants to optimise economic value
Published: 2019-01-08
Subjects: Civil and Environmental Engineering, Computational Engineering, Engineering, Hydraulic Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tidal range renewable power plants have the capacity to deliver predictable energy to the electricity grid, subject to the known variability of the tides. Tidal power plants inherently feature advantages that characterise hydro-power more generally, including a lifetime exceeding alternative renewable energy technologies and relatively low Operation & Maintenance costs. Nevertheless, the [...]
Intensity-Duration-Frequency curves at the global scale
Published: 2018-12-18
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydraulic Engineering, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Water Resource Management
Intensity-Duration-Frequency (IDF) curves usefully quantify extreme precipitation over various durations and return periods for engineering design. Unfortunately, sparse, infrequent or short observations hinder the creation of robust IDF curves in many locations. This paper presents the first global, multi-temporal (1 to 360 hours) dataset of Generalized Extreme Value (GEV) parameters at 31 km [...]
Evaluation of open-access global digital elevation models (AW3D30, SRTM and ASTER) for flood modelling purposes
Published: 2018-06-25
Subjects: Aerospace Engineering, Civil and Environmental Engineering, Computational Engineering, Computer Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydraulic Engineering, Hydrology, Life Sciences, Physical Sciences and Mathematics, Water Resource Management
Digital Elevation Models (DEM) are a key piece of information for the accurate representation of topographic controls exerted in hydrologic and hydraulic models. Many practitioners rely on open-access global datasets usually obtained from space-borne survey due to the cost and sparse coverage of sources of higher resolution. In may 2016 the Japan Aerospace eXploration Agency publicly released an [...]
Optimising tidal range power plant operation
Published: 2017-12-11
Subjects: Civil and Environmental Engineering, Civil Engineering, Computational Engineering, Electrical and Computer Engineering, Engineering, Hydraulic Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Power and Energy
Tidal range power plants represent an attractive approach for the large-scale generation of electricity from the marine environment. Even though the tides and by extension the available energy resource are predictable, they are also variable in time. This variability poses a challenge regarding the optimal transient control of power plants. Here we consider simulation methods which include the [...]
Comparison of 0-D, 1-D and 2-D model capabilities for tidal range energy resource assessments
Published: 2017-11-22
Subjects: Civil and Environmental Engineering, Computational Engineering, Earth Sciences, Electrical and Computer Engineering, Engineering, Environmental Sciences, Hydraulic Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Power and Energy
Tidal range energy projects present an attractive means for the predictable and large-scale generation of electricity from the marine environment. In particular, proposals are under consideration in UK waters, with their feasibility currently being under high levels of scrutiny. This is due to a combination of potential environmental and socio-economic impacts that are challenging to quantify in [...]
Computationally Efficient Tsunami Modelling on Graphics Processing Units (GPU)
Published: 2017-11-13
Subjects: Applied Mathematics, Civil and Environmental Engineering, Civil Engineering, Computer Sciences, Earth Sciences, Engineering, Environmental Sciences, Geophysics and Seismology, Hydraulic Engineering, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Other Civil and Environmental Engineering, Other Earth Sciences, Other Environmental Sciences, Physical Sciences and Mathematics
Tsunamis generated by earthquakes commonly propagate as long waves in the deep ocean and develop into sharp-fronted surges moving rapidly towards the coast in shallow water, which may be effectively simulated by hydrodynamic models solving the nonlinear shallow water equations (SWEs). However, most of the existing tsunami models suffer from long simulation time for large-scale real-world [...]
Compositional Signatures in Acoustic Backscatter Over Vegetated and Unvegetated Mixed Sand-Gravel Riverbeds
Published: 2017-11-02
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Monitoring, Environmental Sciences, Geomorphology, Hydraulic Engineering, Physical Sciences and Mathematics, Statistical Models, Statistics and Probability
Multibeam acoustic backscatter has considerable utility for remote characterization of spatially heterogeneous bed sediment composition over vegetated and unvegetated riverbeds of mixed sand and gravel. However, the use of high-frequency, decimeter-resolution acoustic backscatter for sediment classification in shallow water is hampered by significant topographic contamination of the signal. In [...]