Importing FMU into Simcenter Flomaster 1D Simulation

Simcenter Flomaster provides numerous sample systems as pre-defined templates. You start the Flomaster model from the sample system Ship to Shore, which models a typical issue caused by sudden movement of water.

To load the sample system, Ship to Shore:
1. Launch Simcenter Flomaster version 2021.2 or later.
2. Select the Tools > Sample Systems > Ship to Shore system and click UNPACK.
3. In the pop-up dialog, accept the default settings and select UNPACK.
4. In the Networks tab, to open the 1D network, double-click the Flomaster > Sample Systems > Ship to Shore icon.
  The flows coming from valves 60,8,61 and from valves 62,9,63 are replaced by the FMU component that you exported from Simcenter STAR-CCM+. This FMU represents the four-armed junction.

In the starting files, a pre-defined four-armed junction component is available in which flow enters through three inlets, merges at a junction, and leaves through the outlet. In Simcenter Flomaster, because there is no built-in data for pressure drops in such a component, you import the surrogate model from Simcenter STAR-CCM+ and configure it appropriately.

To load the pre-defined component,
1. Select File > Unpack.
2. In the pop-up dialog, select the four_armed_junction_noConnection.FMPck from the starting files and click Open.
3. Accept the default settings and click Unpack.
The pre-defined component can be viewed within the Catalogues tab, Components > User-defined > Composite Components > four_armed_junction_noConnection node.

You import the surrogate model and embed it into the pre-defined component to create a fully defined four-armed junction.

To load the FMU file from Simcenter STAR-CCM+:

Select the Launchpad tab from the toolbar.
In the launchpad, select the Systems > Component tab and choose New FMU Component.
In the opened FMU Component Wizard, select the junction_surrogates.fmu file exported from the design study and click CREATE.

In the Component Customisation Form, accept default settings and click OK.

Note	Simcenter Flomaster uses SI units. In the case of non-SI units, the variables from the FMU file must be converted in Flomaster using unit converters.

The imported surrogate can be viewed within the Catalogues tab, Components > User-defined > junction_surrogates.

To connect the FMU component junction_surrogates into the pre-defined component:

Double-click the Components > User-defined > Composite Components > four_armed_junction_noConnection node to open the network of this component.
Select the junction_surrogates node and drag it into the open network.
You can rotate the component clockwise using the button from the toolbar.
To set up the mass flow balance, first connect Inlets (16,17,18) mass flow to Gauge Template controllers (5,6,7) as Measure Input, selecting Mass Flow Rate Result feature in the pop-up feature list.
Afterwards, connect the Output Signals of the Gauge Template controllers(5,6,7) to the 3 Arm Sum controller (15) as Input Signals.
When connecting Inlets (16,17,18) to the FMU component (1), select the corresponding variable.

Connect the Output Signals of Gauge Template controllers(5,6,7) to the

FMU component (1) with the corresponding variable selection:

Gauge Template Controller Number	FMU Variable
5	Mass Flow 1
6	Mass Flow 2
7	Mass Flow 3

Connect the Output Signal of the 3 Arm Sum controller (15) to the signal port Mass Flow Rate of the Source: Flow controller (9).
To set up pressure in the system, first connect the pressure from Hydraulic Node 4 to each Summing Junction controller (10,12,14) as one Input Signal.
The pressure circuit goes from the outlet towards the inlets. When making the connection, select the Hydraulic Node Results: Pressure as the feature.

Add the pressure differences coming from FMU component (1) to the Summing Junction controllers (10,12,14) as the second Input Signals.

When connecting the FMU component (1) to Summing Junction controllers (10,12,14), select the corresponding variable from the following table:

Summing Junction Number	FMU Variable
10	Surrogate_SA_Total_Pressure_Inlet1
12	Surrogate_SA_Total_Pressure_Inlet2
14	Surrogate_SA_Total_Pressure_Inlet3

Connect the Output Signals of the Summing Junction controllers (10,12,14) to the Pressure port of the Source: Pressure controllers (2,3,4) at the three inlets.

The fully connected network of the four armed junction component is shown below:

After connecting the four-armed junction in the previous step, you define the component including the FMU as a new composite component. You can apply a composite component multiple times in the final network of the ship to shore system — wherever four-armed junctions are required.

To define a new composite component:
1. In the open network of the completed four-armed junction, click and drag to select all the elements using a bounding box.
2. Right-click on any element and select Extract Selection to Composite.
  A New Composite Component appears in the Components > User-defined node.
3. Select the Name of this component property list and rename it to four_armed_junction_connected.
4. To define the signal ports of this component, double-click to open the network of the component.
5. In the Network View property window, select the Connections tab and click Deduce.
  Flomaster derives the ports from the rest of the system. The signal ports of this component are therefore mapped automatically.
6. To arrange the Graphical Port Replacement, select the Connections tab and click Graphical View at the bottom.
  In the opened window, drag arms 1,2,3 to the left hand side and arm 4 to the right hand side as shown in the image below:
In the network Ship to Shore Model, you place the four_armed_junction_connected component twice.
1. To open the network, in the Networks tab, double-click the Ship to Shore Model to open the network.
2. Delete the 6 connections from Valves (60,8,61,62,9,63).
3. In the Catalogues tab, select the Components > User-defined > four_armed_junction_connected component and drag and drop it twice in the Ship to Shore Model.
4. Connect the Valves (60,8,61) to the first four_armed_junction_connected component (34) without selecting any variables and Hydraulic Node (82) to the 4th port of the component.
5. Connect the Valves (62,9,63) to the second four_armed_junction_connected component (39) without selecting any variables and Hydraulic Node (82) to the 4th port of the component.
The new Ship to Shore Model is shown below: