This is a guide on migrating MIKE 11 or MIKE HYDRO River models into MIKE+.
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The process of migrating a MIKE 11 or MIKE HYDRO River model into MIKE+ involves the following key steps:
# 01 Check model validity with the MIKE 1D engine
Ensure your model functions with the latest release of MIKE 11 or MIKE HYDRO River and can be executed using the MIKE 1D engine.
Confirm functionality using the latest release of MIKE 11 or MIKE HYDRO River
Install the latest version of MIKE Zero and open the MIKE 11 or MIKE HYDRO River setups in the program. Check and correct any validation errors then launch a simulation using the setup.
Confirm execution with MIKE 1D
MIKE+ uses the MIKE 1D engine for hydrodynamic computations. This is the new 1D computational engine for modelling unsteady flows in pipe networks, river networks, and estuaries. It replaces the MIKE 11 engine for river networks.
Both the MIKE 1D and MIKE 11 engines have the same fundamental bases, i.e., solution of the one-dimensional shallow water equations (Saint Venant equations). However, there are some differences in the implementation of certain solutions in the codes resulting in differences in model results.
As such, one of the first steps when migrating an earlier model to MIKE+ is to ensure that calculations with the earlier setup, especially when built in MIKE 11, can be executed using the MIKE 1D engine.
- In MIKE 11, launch a MIKE 1D simulation on the Start tab page of the Simulation Editor (Fig. 1)
- MIKE HYDRO River already uses the MIKE 1D engine, and thus, you simply need to ensure the model is functioning and can be executed
Fig. 1 - The Start tab page of the MIKE 11 Simulation Editor
Ensure it produces comparable results
If the MIKE 11 engine was being used for computations with the earlier setup, confirm the model results using the MIKE 1D engine are consistent with earlier results. Below is a basic list of items to check in the comparison:
Examine simulation summaries. First, check simulation summaries from successful simulation runs to compare overall system inflows, outflows, and storages. Potential differences in system inflows (e.g., runoff, network inflows) and outflows are easily apparent in the summaries.
Compare outlet discharges. Next, plot discharge time series results at network outlets and tributary ends to systematically trace potential causes of deviation from earlier results.
Check implemented controls. Lastly, if Control Structures are present in the model, compare implemented control strategies for controlled structures over the simulation period to check for a similar interpretation of set rules.
The above checks can help narrow down model components causing differences between computed results with the MIKE 11 and MIKE 1D engines. For example, differences in computed runoff that are subsequently used as input to the network will be readily apparent from simulation summaries. Thus, further checks and corrections may only need to involve the runoff model component and not the entire system.
# 02 Import your model into MIKE+
Ready-made options are available for fully importing MIKE 11 or MIKE HYDRO River models into MIKE+.
Follow the steps below for a smooth model import:
First, create a new MIKE+ project for your river model. Define a Coordinate System for the MIKE+ project before performing the full import.
Then, import full MIKE 11 or MIKE HYDRO River setups into MIKE+ using the Importer tools offered under the File menu (Fig. 2). Note that when importing MIKE 11 model setups into MIKE+, the MIKE 11 model is first internally converted into a MIKE HYDRO River setup before the import.
Fig. 2 - Options for important earlier river models into MIKE+
Finally, review the process log displayed at the bottom of the MIKE+ window (Fig. 3) to
a) check how the data has been imported into MIKE+ and to
b) verify unsupported items not reflected in the new MIKE+ model. Warnings and important notes about the import are displayed in yellow text, while errors are displayed in red.
Also, the validation tools in MIKE+ help indicate potential setup errors from the import and reveal earlier configuration issues that went undetected in other software. MIKE+ has stricter requirements on data input than MIKE 11 or MIKE HYDRO River. Data errors are highlighted in red in the editors and the corresponding sections in the Setup Tree marked with an ‘x.’
Fig. 3 - Log View window in MIKE+
The import of full river model setups into MIKE+ using the options shown in Fig. 2 performs an Append operation of data into the database. Thus, repeating the import into the same MIKE+ project may lead to record duplications.
# 03 Ensure the validity of your new MIKE+ model
Follow the steps below in sequence to finalize the migration of the MIKE 11 or MIKE HYDRO River model into MIKE+:
- In MIKE+, check and correct setup validation errors detected after the import. MIKE+ has, in general, stricter requirements on data input than MIKE 11 or MIKE HYDRO River
- Confirm setup components are complete, as expected, and that custom computation parameters match what was previously specified. Some data may have been converted during import therefore you’ll need to check how the data has been imported into MIKE+
A key item to check is the MIKE+ MIKE 1D Engine Configuration editor (Fig. 4), which enables the modification of predefined and custom parameters for the computation engine. Configure parameters specific to river models under the HD River section, if necessary.
Fig. 4 - The MIKE 1D Engine Configuration editor in MIKE+
Items that have been modified from Default are highlighted in red, with the values automatically updated during the full setup import. These shall correspond to settings defined in the earlier model – either in the Computation Control Parameters editor in MIKE HYDRO River, or the Hydrodynamic Parameters editor in MIKE 11 (Fig. 5).
Fig. 5 - The MIKE HYDRO River Computation Control Parameters editor (left), and the Hydrodynamic Parameters editor in MIKE 11 (right)
Run a simulation with the current setup in MIKE+. The same simulation setup active in the earlier model is automatically defined in the imported setup in MIKE+.
Confirm the MIKE+ model produces results consistent with those from the earlier model. Check items as mentioned in # 01, i.e., Check simulation summaries, Compare outlet discharges, and Check implemented controls (if any), from results.
Recalibrate the model, if necessary. Assuming that, from previous steps, configuration issues from the import had been checked and corrected as necessary, recalibration of the migrated model may be expected depending on the engine used in the earlier model.
If the MIKE 11 engine had been used for the earlier model, some differences are expected in the results as differences exist between the MIKE 11 engine and the MIKE 1D engine, which MIKE+ uses. If the MIKE 1D engine has been previously used, small changes may occur because of improvements to the MIKE 1D engine in subsequent software releases.
Tools are readily available to support a smooth migration of full setups of MIKE 11 and MIKE HYDRO River models into MIKE+. This process involves more than just transferring data from one modelling platform to another in order to retain the integrity of the migrated mode. We encourage you to:
- Watch out for set-up and configuration issues that have gone undetected in the MIKE 11 or MIKE HYDRO River model
- Be systematic and reasonable in comparing results between models. Understand there are expected differences in the set-up and execution of models between MIKE+ and MIKE 11/MIKE HYDRO River modelling software
MIKE+ – Getting started with river modelling