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Il presente volume digitale ad accesso libero (licenza Creative Commons 4.0) raccoglie le memorie brevi pervenute al Comitato Scientifico di IDRA16 ed accettate per la presentazione al convegno a valle di un processo di revisione tra pari. Il volume articola dette memorie in sette macro-tematiche, che costituiscono i capitoli del volume stesso: I. meccanica dei fluidi; II. ambiente marittimo e costiero; III. criteri, metodi e modelli per l’analisi dei processi idrologici e la gestione delle acque; IV. gestione e tutela dei corpi idrici e degli ecosistemi; V. valutazione e mitigazione del rischio idrologico e idraulico; VI. dinamiche acqua-società: sviluppo sostenibile e gestione del territorio; VII. monitoraggio, open-data e software libero. Ciascuna macro-tematica raggruppa più sessioni specialistiche autonome sviluppatesi in parallelo durante le giornate del Convegno, i cui titoli vengono richiamati all’interno del presente volume. La vastità e la diversità delle tematiche affrontate, che ben rappresentano la complessità delle numerose sfide dell’Ingegneria delle Acque, appaiono evidenti dalla consultazione dell’insieme di memorie brevi presentate.

The presence of some organic and inorganic contaminants in surface water is a longstanding problem in many countries. Contaminants may reach surface waters, accidentally or intentionally; via agricultural activities or from sewage discharges and they may represent a risk for human, animal and vegetable health. The recent development of ICT technologies and innovative sensors can offer novel opportunities to mitigate these risks helping the relevant authorities to discover the cause of the contamination. In particular, the availability on the market of wireless solutions to connect a large on-line sensor network, coupled with the simulation software to analyze big data in almost real-time, offer opportunities to develop early-warning systems for the protection of surface waters. In this paper, a first preliminary study to design a smart integrated system able to localize one or more emission sources of contaminant is presented. It is considered a scenario in which each biosensor is able to detect the position, magnitude, lifespan and time of the contamination source in a reach enclosed between two biosensors. A possible sensor suitable for the realization of such a smart monitoring system might be a biosensor based on a Quartz Crystal Microbalances (QCM) functionalized with antibodies through a novel immobilization technique, the Photonic Immobilization Technique (PIT). In fact, this biosensor has the high sensitivity typical of QCM coupled to the intrinsic specificity warranted by the antibodies. The biosensors based on QCMs are very cheap and, consequently, could be installed in many sections of a river thus implementing a large monitoring network.

"On October 23, 2007, the European Parliament approved the ‘Floods Directive’ 2007\/60\/CE (FD), aimed to regulate the procedures for hydraulic risk assessment. One of its most innovative aspects consists in the characterization of flood hazard by multi-scenario hydraulic analyses, based on the estimation of flow velocities and water depths all over the flooded areas. In principle, the accurate evaluation of these parameters would require a complete analysis of the watershed hydraulics, based on two- or even three-dimensional modeling; the latter, however, may hardly be applied to river-scale problems due to its huge computational and input data requirements, so 1D and 2D analyses represent the practical alternatives for fluvial hydraulic investigation. Within this perspective, the systematic comparison between these two modeling approaches provides a valuable help to the user in the confident choice of a tradeoff between complexity and accuracy. The present work discusses a comprehensive comparison between the results of 1D and 2D approaches in the analysis of floods in meandering channels. In particular, both numerical models were applied to a typical river morphology which may be represented by a few shape parameters (e.g. sinuosity, depth\/width ratio, cross-section shape and so on). Conformingly to the common praxis for hydraulic risk assessments, steady flow conditions have been assumed. From the computational point of view, normal-flow framework is considered for the 1D analysis, whereas two-dimensional modeling is performed using CCHE2D, a finite element depth-averaged model developed at NCCHE, the University of Mississippi .. Various channels with different shape parameters (namely sinuosity and depth\/width ratio) are considered, according to their typical values for natural rivers. For each combination of shape parameters, several simulations are performed to produce in-bank and overbank flows. The models results are compared in terms of flow velocity, free surface elevation, shear stress distribution and computed stage-discharge hydrograph. Finally, the values of the minimum freeboard (defined as the minimum distance between water surface and the top of river bank) across the channel bend are evaluated and compared."

For unsteady flow problems, such as propagation of flood waves in open channels, simplified models, know as kinematic, diffusion and quasi-steady, are widely used instead of solving the full dynamic model. In order to correctly use these models, it is mandatory to define the conditions in which they may be applied. The present paper investigate the applicability conditions of the kinematic, diffusion and quasi-steady dynamic shallow wave models for mud flows, modeled as a power law fluid. In the framework of a linear analysis, the applicability ranges are defined by comparing the propagation characteristics of a sinusoidal perturbation to the initial steady uniform flow predicted by the simplified models with those of the full dynamic one. The present results provide guidelines for selecting an appropriate approximation for modeling unsteady power law fluid flow problems and they may represent a useful tool for engineering predictions.

The paper introduces a 2D depth averaged model for the analysis of river morphodynamics, based on a two-phase formulation. Mass and momentum conservation principles are separately imposed for both phases. The model naturally accounts for unsteady non-equilibrium solid transport, since neither instantaneous adaptation hypothesis nor any ad hoc differential equation is employed to represent sediment dynamics. Results from numerical simulations for a 2D test-case are compared with literature experimental data and with available numerical solutions.