Using ReFH2 to Generate TUFLOW Boundary Inputs: Difference between revisions

Content deleted Content added
 
(8 intermediate revisions by 4 users not shown)
Line 1:
=Introduction=
 
Originally published in 1999, and subject to continuous development, the Flood Estimation Handbook (FEH) comprises the standard methods for estimating flood frequency. The rainfall-runoff model is one of two core handbook methods. In 2015, the Centre of Ecology and Hydrology (CEH) and Wallingford Hydro Solutions (httphttps://www.hydrosolutions.co.uk) released a new version of the Revitalised Flood Hydrograph rainfall-runoff model (ReFH2) which allows users to generate design flows and hydrographs from given rainfall events for both catchment and development sites. ReFH2 is a rainfall-runoff model specifically applicable to the UK. It takes inputs from the FEH2013 web service (https://fehweb.ceh.ac.uk), and generates design rainfall events and provides a method for calculating design runoff from sites or contributing subcatchments.
For a full description of the approaches, the reader is referred to their guidance which can be freely accessed at:-
https://www.hydrosolutions.co.uk/support/refh2_faq/refh2_literature/. The ReFH2 method is available within the ReFH2 software. To use ReFH2, the software must be installed locally and a licence must be obtained from Wallingford HydroSolutions. The ReFH2 software can be installed from httphttps://files.hydrosolutions.co.uk/refh2/latest.
<br>
 
Line 11:
 
=ReFH2 Runoff=
The first version of ReFH was first published in 2005 by Kjeldsen ''et al.''[[#References|<sup>1</sup>]].
as a replacement for the original FEH rainfall-runoff method, the FSR/FEH rainfall-runoff method [[#References|<sup>2</sup>]]
. ReFH2 is the most up-to-date implementation of the methods for the calculation of runoff. Improvements include a mass balance closure improvement to the runoff model and updates to the initial conditions, BF0 and Cini (initial baseflow and initial soil moisture, C, respectively). The data contained in the XML from the FEH2013 Web Service also provides the catchment descriptors to calculate the necessary model parameters within ReFH 2 from which the runoff hydrograph is developed.
<br>
Line 56:
[[File:Catchment_Descriptors_Key.png]]<br>
<br>
The model parameters section allows the user to specify the seasonality and other parameters, again for sensitivity analysis. Changing the seasonality will change the seasonal correction factor for the rainfall (and in a future version initial conditions).<br>
<br>
[[File:Model_Parameters.png]]<br>
Line 68:
[[File:ReFH2 Outputs.png]]<br>
<br>
The relevant data can then be copied into the TUFLOW bc_dbase folder and referenced by the '''bc_dbase.csv''' file as appropriate (see [[Tutorial Module08Tutorial_M06|Module 86]] for an example of applying direct rainfall boundary conditions for example).
The gross design rainfall or total net rainfall can be applied to directly to the 2D domain using a 2D_RF polygon to distribute the rainfall. Multiple RF polygons can be used to spatially distribute the rainfall if required.
The total runoff (or rainfall) can be applied directly to a 2D_SA polygon, to apply the inflow to an area of the 2D mesh. There are a number of options for distributing flows in this instance, these are:-
Line 104:
<br>
 
Once the bc_base has been set up then a '''.tef''' file can be generated which populates the ARI variable above with the relevant ARI for the specific question. The '''TEF''' file also creates anewa new output folder for each return period.
 
<br>
Line 121:
=Summary=
 
This post provides instructions of how to obtain direct rainfall and inflow inputs from the ReFH2 software for use within a TUFLOW model. This requires the input of data from the FEH Web Service and the selection of the appropriate return period/duration combinations of which the user is interested. This outputs the time-varying rainfall and total runoff (as well as runoff contributions) which can be exported for use within TUFLOW. It is also possible to use TUFLOW event files to increase efficiency when creating models for multiple return period/duration combinations. FutureA developmentReFH2 into thisTUFLOW areatool willis lookavailable tofor automatethe someQGIS ofTUFLOW thisViewer processplugin, bymore interactingdetails withcan be found on the [[QGIS_ReFH2_to_TUFLOW | QGIS ReFH2 directlyto TUFLOW]] page.
 
=References=