Search results for "Idrologia"
showing 10 items of 508 documents
EHSMu: a new conceptual model for hourly discharge simulation under ecohydrological framework in urban area
2013
A parsimonious conceptual lumped model is presented here with the aim of simulating hourly discharge in urban areas. The EHSMu (EcoHydrological Streamflow Model for urban areas) is able to reproduce the discharge at the outlet of an urban drainage system and, at the same time, soil moisture dynamics and evapotranspirative fluxes over vegetated areas within an urban catchment. In urban areas, rain falling over impervious surfaces is directly transferred towards the drainage system in a time depending on the catchment characteristics, and drainage network geometry. If the rain falls over pervious and vegetated areas the runoff generation is driven by soil moisture content, which in turn is li…
Un tool per la previsione dei livelli invasati e la gestione dei serbatoi siciliani in condizioni emergenziali
2018
L'acqua è una risorsa naturale molto preziosa ma, purtroppo, anche limitata. Anche le aree del mondo che hanno una notevole disponibilità di risorse idriche, a causa dei sempre crescenti consumi della società moderna, rischiano di andare in contro a scenari sempre più critici. A cavallo tra il 2017 e il 2018 la Sicilia è stata investita da un forte evento siccitoso che ha portato gli invasi siciliani, le cui acque vengono utilizzate per scopi irrigui e civili, a rimanere letteralmente vuoti per parecchio tempo. Nei grandi otto invasi del territorio siciliano si è arrivati ad avere appena 40 Mm3 d’acqua, a fronte dei quasi 1.000 Mm3 che rappresentano la capacità d’invaso globale di tutti gli…
Modellazione matematica delle oscillazioni di pressione nella pressurizzazione di un condotto fognario
2006
Si esamina il transitorio di pressurizzazione di un condotto fognario, un fenomeno abbastanza frequente nelle reti di drenaggio urbano. Durante tale transitorio si attuano delle intense oscillazioni di pressione, solitamente interpretate addirittura come “fenomeni di colpo d’ariete” e ritenute in grado di danneggia-re la rete. La natura di tali oscillazioni non è ancora chiara, anche se esse sono generalmente imputate, con modalità non definite, alla interferenza fra la corrente liquida e le sacche d’aria di notevoli dimen-sioni imprigionate dalla corrente liquida contro il cielo del condotto. Nella presente memoria, sulla base di precedenti esperienze di laboratorio, si affronta la modella…
Uncertainty evaluation of design rainfall for urban flood risk analysis
2011
A reliable and long dataset describing urban flood locations, volumes and depths would be an ideal prerequisite for assessing flood frequency distributions. However, data are often piecemeal and long-term hydraulic modelling is often adopted to estimate floods from historical rainfall series. Long-term modelling approaches are time- and resource-consuming, and synthetically designed rainfalls are often used to estimate flood frequencies. The present paper aimsto assess the uncertainty of such an approach and for suggesting improvements in thedefinition of synthetic rainfall data for flooding frequency analysis. According to this aim, a multivariate statistical analysis based on a copulameth…
Probabilistic Flood Hazard Mapping Using Bivariate Analysis Based on Copulas
2017
This study presents a methodology to extract probabilistic flood hazard maps in an area subject to flood risk, taking into account uncertainties in the definition of design hydrographs. Particularly, the authors present a new method to produce probabilistic inundation and flood hazard maps in which the hydrological input (i.e., synthetic flood design event) to a 2D hydraulic model has been obtained by using a bivariate statistical analysis (copulas) to generate flood peak discharges and volumes. This study also aims to quantify the contribution of boundary conditions’ uncertainty in order to evaluate the effect of this uncertainty source on probabilistic flood hazard mapping. Different comb…
Combining a data-driven approach with seasonal forecast data to predict reservoir water volume in the Mediterranean area
2023
Prolonged droughts and water scarcity have become more frequent in recent years, exacerbating the problem of the artificial reservoirs management in the Mediterranean area. This study proposes a methodology which combines a Nonlinear AutoRegressive network with eXogenous input (NARX) data-driven model with Seasonal Forecasts (SFs) data, with the aim to predict the water volume stored in reservoirs at a mid-term scale, as requested by the local authority. The methodology is applied to four Sicilian reservoirs that experienced water scarcity in the recent past. SFs produced at the European Centre for Medium-Range Weather Forecasting are used to force the NARX models. Also, the reservoirs are …
The synergy of water quality and sea surface currents data in determining the spatio-temporal evolution of large-scale circulation features
2014
Chlorophyll-a (CHL-a) and Sea Surface Temperature (SST), amongst others, are proxies or indicators for water quality and can be easily retrieved synoptically and almost in near-real time through satellite remote-sensing. However, as they evolve in space and time in response to winds and currents, a full resolution of the temporal and spatial scales of these latters is required and their influence in shaping the distribution of water quality parameters needs to be assessed. While providing synoptic views and revealing mesoscale features, satellites suffer, indeed, from inadequate representation of sub-grid physical processes and lack of temporal resolution. Conventional point-wise measuremen…
Optical techniques: non-intrusive river monitoring approach
2022
<p>Technological advances over last decades gave an innovative impulse to development of new streamflow measurements techniques, making possible to implement remote flow monitoring methods that allow for non-intrusive measurements. Here, we focus on image-based techniques that involve the use of digital camera, either installed on a bridge or equipped by a drone (UAVs – Unmanned Aerial Vehicles). The most widely known and used optical techniques are the Large-Scale Particle Image Velocimetry and the Large-Scale Particle Tracking Velocimetry. Optical techniques are based on four main steps: (i) seeding and recording, (ii) images pre-processing, (iii) images proces…
Comparison between Entropy and Resilience as Indirect Measures of Reliability in the Framework of Water Distribution Network Design
2014
Abstract The aim of this paper is to investigate which between the entropy and resilience indices represents a better indirect measure of reliability in the framework of water distribution network design. The methodology adopted consisted of (a) multi-objective optimizations performed in order to minimize costs and maximize reliability, expressed by means of one of the indirect indices at time; (b) retrospective performance assessment of the solutions of Pareto fronts obtained. Two case studies of different topological complexity were considered. Results showed that indices based on energetic concepts (resilience and modified resilience) represent a better compact estimate of reliability th…
Improving operation of a complex headworks system for municipal use and hydropower production by mathematical programming
2013
The paper presents a Mixed Integer Non Linear Programming (MINLP) model of the water resources system supplying Genoa, in northern Italy. The system presently features five reservoirs, three main river intakes, and two well fields. The hydrological regime is typically Mediterranean; water availability is however relatively abundant, so that drought issues are limited, especially now that water demand from the supply sources has decreased due to reduced population, deindustrialization and to improvement in the operation and maintenance of the water distribution network. In this context, it is worthwhile considering the possibility to relax an over-conservative management of resources, justif…