Showing papers by "Slobodan Djordjević published in 2017"

A new experiments-based methodology to define the stability threshold for any vehicle exposed to flooding

Abstract: A vehicle exposed to flooding, after losing stability, becomes buoyant and may be washed away with potential injuries and fatalities. Such vehicles cause additional disruption to traffic that is already affected by flooding, which may lead to substantial indirect economic impact, especially in urban areas. Therefore, the analysis of the stability of vehicles exposed to flooding is important in order to make decisions to reduce damages and hazards. In this research, based on an experimental campaign that included a range of twelve car models, a new methodology to obtain the stability threshold for any real vehicle exposed to flooding is developed. A stability coefficient (SCmod) is derived with which the vehicles can be sorted by stability against water flows and their stability functions may be determined. The experiments were conducted with three different model scales (1:14, 1:18 and 1:24) and involved analysis of both friction and buoyancy effects, which made this the most comprehensive researc...

A comparison of three dual drainage models: shallow water vs local inertial vs diffusive wave

Abstract: In this study we compared three overland flow models, a full dynamic model (shallow water equation), a local inertial equations model (gravity wave model), and a diffusive wave model (parallel diffusive wave model). The three models are coupled with the same full dynamic sewer network model (SIPSON). We adopted the volume exchange between sewer and overland flow models, and the hydraulic head and discharge rates at the linked manholes to evaluate differences between the models. For that purpose we developed a novel methodology based on RGB scale. The test results of a real case study show a close agreement between coupled models in terms of the extents of flooding, depth and volume exchanged, despite highly complex flows and geometries. The diffusive wave model gives slightly higher maximum flood depths and a slower propagation of the flood front when compared to the other two models. The local inertial model shows to a slight extent higher depths downstream as the wave front is slower than the one in the fully dynamic model. Overall, the simplified overland models can produce comparable results to fully dynamic models with less computational cost.

Validation of 2D shock capturing flood models around a surcharging manhole

Abstract: This work offers a detailed validation of finite volume (FV) flood models in the case where horizontal floodplain flow is affected by sewer surcharge flow via a manhole. The FV numerical solution of the 2D shallow water equations is considered based on two approximate Riemann solvers, HLLC and Roe, on both quadrilateral structured and triangular unstructured mesh-types. The models are validated against a high resolution experimental data-set obtained using a physical model of a sewer system linked to a floodplain via a manhole. It was verified that the sensitivity of the models is inversely proportional to the surcharged flow/surface inflow ratio, and therefore requires more calibration from the user especially when concerned with localised modelling of sewer-to-floodplain flow. Our findings provide novel evidence that shock capturing FV-based flood models are applicable to simulate localised sewer-to-floodplain flow interaction.

Scour and hydrodynamic effects of debris blockage at masonry bridges: insights from experimental and numerical modelling

Abstract: The research presented in this paper was supported by funding from the UK’s Engineering and Physical Sciences Research Council (EPSRC) under grant EP/M017354/1.

Experimental investigation of the influence of manhole grates on drainage flows in urban flooding conditions

Abstract: 1 University of Sheffield, Department of Civil and Structural Engineering, Sir Frederick Mappin Building, Mappin Street, Sheffield, S1 3JD, UK 2 MARE Marine and Environmental Sciences Centre, Department of Civil Engineering, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra, Portugal 3 IMAR Institute of Marine Research, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra, Portugal 4 Department of Civil, Geo and Environmental Engineering, Chair of Hydrology and River Basin Management, Technical University of Munich, Arcisstrasse 21, 80333 Munich, Germany 5 Centre for Water Systems, University of Exeter, North Park Road, Exeter EX4 4QF, UK * Corresponding author’s e-mail: m.rubinato@sheffield.ac.uk

Interactive 3D visualisation of flood impact to critical infrastructure

Abstract: The work presented in this paper was partially funded by the ongoing H2020 EC project EU-CIRCLE (2015-2018), GA 653824.