PE8_4 Computational engineering

Under unprecedented pressure from urbanization and climate change, an ever increasing number of streams worldwide fails to meet good ecological status, thus threatening water quality and ecology, and severely impacting our territories. In this vein, RiverWatch aims to develop a new disruptive monitoring infrastructure for river systems focused on the transport of buoyant plastics, woody material, and floating pollution. The infrastructure will build on current knowledge in image-based hydrological monitoring to explore novel advancements in unsupervised computer vision techniques for environmental analyses. RiverWatch will exploit camera systems on fixed stations as well as volunteer smartphones to build a dense network of monitoring stations potentially along any river system in the world. This may help to overcome the current limitations in the management and maintenance of high cost installations and at the same time allow us to expand our monitoring capabilities. Towards establishing a robust infrastructure, RiverWatch will focus on the Sarno River to develop a dense monitoring system based on cutting-edge unsupervised computer vision.

Notably, the Sarno River is the most polluted river in Europe and a challenging and socially disadvantaged environment to establish monitoring networks. A custom-built mobile app as well as advanced image-based algorithms will be developed to process footage captured by citizens and fixed cameras and collected at a remote server. Image-based algorithms will enable analysis of the river flow along with the estimation of surface pollutants discharge and their characterization. Such data will be published in close to real-time on a web-Gis online platform featuring a storymap and a public database. High-frequency data at several locations in the drainage network will facilitate implementation of simple modeling tools to describe and forecast pollutant transport in the Sarno watershed. RiverWatch objectives will be achieved through the harmonized effort of a multidisciplinary research team with a past experience of collaboration in environmental monitoring through computer vision and machine learning as well as citizen science. The transformative potential of the project is expected to enrich the monitoring tools currently available to National Hydrometric Services and Environmental Agencies worldwide by providing an easy-to-use and inexpensive approach to quantitatively assess river pollution. Finally, RiverWatch will stimulate new research on the pollution dynamics in river watersheds and on the interactions of pollutant transport with climate and anthropic agents.

Bridges are fundamental elements of our infrastructure system, indispensable for the effective movement of people and goods in territories with varied orography and often high seismic, hydraulic and geomorphological risk. The natural degradation of materials, accelerated by the aggressive environmental conditions, inefficient maintenance and construction flaws are reasons why the current infrastructural heritage requires a great deal of attention in order to identify the most critical situations and prevent the occurrence of adverse events. This proposal has drawn inspiration from recent field experiences in order to select protection, management, and maintenance measures that have immediate applications to real emergency situations. In particular, it is focused on the river flow dynamics, which plays an important role in riverbed morphology. Building a bridge pier along the river alters its cross-section, causing a change in the water flow. These changes are mainly responsible for pier scour that represents the main cause of bridge failures. We propose the application of an innovative device that will act as an intensity damper of the vorticity generated by the complex dynamics occurring at the intersection between the bottom of the channel and the obstacle. BIO-EMBRACE aims at analyzing the flow dynamics at different flow regimes and the boundary conditions between the water flow and the bridge pier, through a novel, hybrid, multiscale approach. The final deliverable of the project will be the design and testing of an innovative device able to eventually reduce scour. We will develop an integrated theoretical-numerical-experimental methodology merging the experience of the partners in their areas of expertise, namely the fluid dynamics simulation and the experimental techniques. The numerical simulations will be conducted both through traditional Computational Fluid Dynamics (CFD), and two particle based numerical methods, the Lattice Boltzmann Method (LBM) and the Smoothed Particle Hydrodynamics (SPH), given the expertise in this field of all the operating units involved. The numerical simulations, appropriately validated, will support the definition of models, which could be easily applied for design purposes.