Guidance for using EPANET_WB as presented in "Comparing alternative PDA solvers with EPANET" (Todini et al., 2022 - Journal of Hydroinformatics, IWA Publishing).


### Introduction ###
EPANET is an open-source software to perform extended period simulations of water distribution systems for both hydraulic and water quality aspects.
In EPANET 2.2 (EPA official release, 2020), a PDA solver was implemented to represent more realistically the hydraulic behaviour of pressurized networks.
In this work, additional PDA solvers were added to EPANET.


### Folders and files ###
- Executables
	- "epanet2.dll" is a dynamic-link library compiled in C: it is the engine of EPANET.
	- "EpanetWorkbench.exe" is the GUI executable of EPANET: it uses "epanet2.dll" as engine.
	- "runepanet.exe" is the command line executable of EPANET: it uses "epanet2.dll" as engine.
- Networks
	It contains the 14 networks used as benchmark in this work: they are EPANET ".inp" input files.
	They can also be opened and modified with Notepad.


### Example of use ###
1. with GUI: just run "EpanetWorkbench.exe". In the Browser panel on the right side of the interface, choose Options from the drop-down menu and double click Hydraulics. In the Demand Model drop-down menu you will find all the algorithms as presented in this work. You can open any ".inp" network from the Networks folder to test them.

2. with command line application: copy any ".inp" input file from the Networks folder and paste it in the Executables folder. Open a command prompt in the Executables folder (e.g. once in the Executables folder, click on the address bar, type "cmd" without quotation marks and press Enter).
Run the command "runepanet name.inp name.rpt" without quotation marks and replacing "name" with the name of the network.
EPANET will generate a ".rpt" report file. If you want to change the algorithm being used, open the ".inp" input file with Notepad, find the OPTIONS section and modify the Demand Model value with any of which presented in this work.

For further details about the use of EPANET GUI or command line application please refer to EPANET 2.2 User Manual at "https://epanet22.readthedocs.io/en/latest/".


### Quick references ###
- "Comparing alternative PDA solvers with EPANET" (Todini et al., 2022 - Journal of Hydroinformatics, IWA Publishing)
- EPANET EPA official release "https://www.epa.gov/water-research/epanet"
- "A Gradient Algorithm for the Analysis of Pipe Networks" (Todini and Pilati, 1988 - Computer Applications in Water Supply, Volume I-Systems analysis and simulation, 1-20, John Wiley & Sons Inc.).


### Differences with EPANET 2.2 (EPA official release, 2020) ###

The main difference with EPANET 2.2 User's Manual lies in the key words used for "DEMAND MODEL" ("Comparing alternative PDA solvers with EPANET" (Todini et al., 2022 - Journal of Hydroinformatics, IWA Publishing)), which was extended to accept additional acronims.

For "DEMAND MODEL" equal to:

- DDA     EPANET_WB will run the Demand Driven Approach without constraints
- PDA     EPANET_WB will run the Pressure Driven Approach using the EPANET 2.2 approach slightly modified referred to as CEM-1 in the paper
- CEM-2   EPANET_WB will run the Pressure Driven Approach using the barrier function approach described in the paper
- GGA     EPANET_WB will run the Pressure Driven Approach using the GGA-PDA approach described in the paper
- ASM     EPANET_WB will run the Pressure Driven Approach using the ASM approach described in the paper


### Authors ###
Professor	Ezio Todini - Italian Hydrological Society, Bologna, Italy
Engineer	Alessandro Farina - University Luigi Vanvitelli, Aversa, Italy
Engineer	Annalaura Gabriele - University of Cassino and Southern Lazio, Cassino, Italy
Professor	Rudy Gargano - University of Cassino and Southern Lazio, Cassino, Italy
Engineer	Lewis A. Rossman - Consulting Engineer, Cincinnati, USA