PoroStrip_v1.0 – A code to compute anisotropic porosity fields for urban flood modelling

Published: 27 June 2020| Version 1 | DOI: 10.17632/47ypvbx9vm.1


This repository contains the code "PoroStrip_v1.0". It allows obtaining the spatially-distributed porosity fields for anisotropic porosity models in differential form, that can be used for simulating large-scale urban floods. The method and its implementation are described in the paper: Ferrari, A., and Viero, D.P., 2020. Floodwater pathways in urban areas: a method to compute porosity fields for anisotropic subgrid models in differential form, Journal of Hydrology 589, 125193, https://doi.org/10.1016/j.jhydrol.2020.125193. The repository also contains the input (and some output) files for the three case studies described in the above paper. This repository contains the following folders: ⇒"Code_Porostrip_v1.0" with the code "PoroStrip_v1.0" available as both compiled and source code. The folder contains: •"Executable" with: -the Win86 executable file "PoroStrip_v1.0.exe"; -the "PoroStrip_v1.0_cfg.txt" configuration file, which determines the output files to be created; •"Source" with the source code (ASCII files), where some routines and intrinsic routine calls are specific for Intel Fortan; •the Intel Fortran project files. ⇒"CaseStudy1_Toce", "CaseStudy2_Spinea", and "CaseStudy3_Palmanova" folders, referring to the case study described in the companion paper. Each case study folder contains: •"input" with the files that have to be provided to the code as inputs: -the .bln file with the coordinates of the obstacle footprints; -the .asc files with the characteristics of the chosen (coarse) grid, structured as the header of ESRI ASCII grid files (xLLcenter, yLLcenter, cellsize, ncols, nrows, NODATA_VALUE); •"ouput" with some of the output files produced by the code for each tested grid size and strip width; •"visualization": the .dxf files produced by the code have been modified with AutoCAD Map3D to produce a .pdf file helpfull for the overall visualization of the results (e.g. location of the obstacles and resulting roseplots of conveyance porosity). The alternative .dxf version generated with AutoCAD is denoted by the "_prnt" suffix ("_prnt.dxf"). The .pdf files have been structured with the following switchable layers: -CELLS showing the (coarse) grid cells (pink-lined squares); -OBSTACLES representing the building footprint (gray areas); -PSI_L showing the L principal direction of maximum conveyance (blue segments); -PSI_T showing the T principal direction othogonal to L (red segments); -ROSEPLOTS representing the Psi roseplots (green lines). ⇒the "Layers_PorosityMaps.las" that can be used to assign proper styles to the AutoDesk AutoCAD layers of the dxf files produced by the "Porostrip_v1.0.exe" code. See also the "README.txt" file contained in this repository.


Steps to reproduce

Instructions to obtain the model results: 1) Put the "PoroStrip_v1.0.exe" executable into the case study folder along with the "PoroStrip_v1.0_cfg.txt" 2) Run the executable; 3) Select the .bln file containing the obstacles footprints; 4) Select the .asc file with the characteristics of the computational grid; 5) Select the method for computing the porosity parameters: 1 for strip-based method, 2 for segment-based method; 6) With reference to the chosen method, specify the strip width (in meters) or the segment spacing (in meters); 7) Enter the angular scan interval (in degrees); suggested value is 1°. The code then computes the four porosity parameters for each cell of the defined grid, and generates the chosen output files within a (new) subfolder. The subfolder and the output files are named as the input .asc file plus information on the method used (strips or segments) and on the strip width (or segment spacing).


Hydraulics, Numerical Algorithm, Numerical Modeling, Flood