A semi‐implicit numerical model for urban drainage systems

Abstract

SUMMARYIn this paper, a semi‐implicit numerical model for one‐dimensional urban drainage networks is formulated in such a fashion as to intrinsically account for arbitrary cross sections, for the occurrence of dry areas, for free surface, and for pressurized flows. The governing differential equations are discretized with a consistent mass conservative scheme that naturally applies to all flow regimes. The resulting mildly nonlinear system, at every time step, is efficiently solved with a converging, properly devised, nested Newton‐type algorithm. It will be shown that with the proposed semi‐implicit model, high accuracy can be achieved at a moderate computational cost. Copyright © 2013 John Wiley & Sons, Ltd.

Semi- vs. Fully-Distributed Urban Stormwater Models: Model Set Up and Comparison with Two Real Case Studies

“…Examples of important advancements are: increase of available data (e.g., digital map [18], advanced collaborative sources of information [19], weather radar data [20]); advances in technology (e.g., remote sensing [21], computing techniques [22]); and improvements of numerical methods (e.g., reduction in simulation times in 2D overland modeling [23], new mathematical approaches [24][25][26]). These improvements are opening the discussion for the application of FD urban stormwater models.…”

Interactive use of simulation models for collaborative knowledge construction

“…For example, new numerical schemes for the computations of overland flow are available that that allow for computation times that are more than 100 times shorter than conventional models (Stelling 2012;Casulli and Stelling 2013). This will not only provide more adequate model outputs, but will also decrease model uncertainties, as ensemble calculation become a serious option.…”

“…0,5 meter by 0,5 meter) and the inclusion of all relevant processes (i.e. overland flow, groundwater flow, canal flow and sewer flow) (Casulli and Stelling 2013). …”

“…This computation core consists of numerical methods to solve the 2D hydraulic equations for water flow, under the conditions of short computation times while still conserving the details of the study area. The technical details of this flood simulation model can be found in Stelling (2013) and in Casulli and Stelling (2013).…”

“…The module is based on the continuity equations and solved with a converging nested Newton-type algorithm. Further details about this method can be found in Casulli and Stelling (2013). All spatial characteristics of the study areas were defined on the level of the subgrids of 0,5 by 0,5 by their elevation, surface roughness, interception, infiltration rate, crop type and the porosity and permeability of the soil, location of canals and ditches, accompanying bottom profiles and roughness and object data of weirs, culverts and pumps.…”