Import design study data from Simcenter STAR-CCM+

The goal of this example is to show a typical workflow when running a simulation to characterize a component using 3D CFD within Simcenter STAR-CCM+ and then use the characterization as a table file within a Simcenter Amesim component.

With Simcenter STAR-CCM+, you can obtain more accurate data on the flow versus pressure drop characteristics of an orifice to feed back into your Simcenter Amesim component from the Hydraulic or Thermal Hydraulic libraries.

Simcenter STAR-CCM+ solves the fluid flow through the orifice at static points for the defined operating range.

The following image shows the 3D geometry:

Figure 66: 3D geometry of the orifice

The 3D CFD model contains the following predefined objects:

• mesh operations

• physics models

• initial conditions (in the physics continuum and at the inlet boundary)

• regions and boundaries

• parameters and reports

The goal is to create the flow characteristics as a function of the pressure drop and fluid temperature at the inlet of the orifice.

Then a sweep study is performed on the inlet pressure and inlet temperature to cover the operating range.

The variations are the following:

• Inlet pressure takes the values 5, 10, 15, and 20 in bar.

• Inlet temperature takes the values 20, 40, and 60 in degC.

Here is the design study:

Figure 67: Design study

Once the study is completed, we can export the design result as .csv.

Figure 68: Export as csv file

Depending on your needs or the components you use in your Simcenter Amesim model, you can create a flow characteristic as a function of the pressure drop for one temperature or a flow characteristic map that takes both the pressure drop and the temperature into account. In this example, we create the flow characterisctic map as a function of the pressure drop and the temperature.

Creating a 2D map flow characteristic

1. In Simcenter Amesim, open Data Import from the Tools menu.

2. Load the csv file you created from Simcenter Star-CCM+ which contains the design results.

Figure 69: Loaded csv

To build the table data file, we are interested in the inlet temperature (column G), the pressure drop (column D), and the mean flow (column B). The 2 inputs of the table are the inlet temperature and the pressure drop, the output of the table is the mean flow. As for a same value of the inlet pressure, the pressure drop is slighty different depending on the inlet temperature, it is easier to create a M1D table format. For each value of the inlet temperature, there is a table of the mean flow as a function of the pressure drop. To generate this M1D table format, we need first to arrange the table and sort the columns of the inputs. That means the lines with the same input temperature values must be gathered and sorted in ascending order; and for each input temperature, the pressure drop values must be sorted in ascending order.

3. In the Table operations section of the File tab, click the drop-down arrow of the Column sort button, and select Advanced sort ...

4. In the Advanced sort dialog, select column G for the first line Sort by column. Then click Add another sort column, and select column D for the added line Then by column.

5. Click the Sort button to confirm your selection. The new sorted table is as follows:

Figure 70: Sorted table

6. Switch to the Selection tab; and in the Table format section, select the M1D table format. We use the slice detection to select the correct cells of the table automatically:

In the Detection range field, indicate the columns to which the detection is applied. First enter the column of the first input that defines each slice; which is the inlet temperature in this case. Then enter the column of the second input; the pressure drop. Finally enter the column of the output; the mean flow.

In the Split slices by drop-down list, select Slice step values, and set the value to 18. The increment for the inlet temperature is 20 degC, so you must use Slice step values for this detection. Setting the value to 18 means that a change in the value column greater than 18 starts a new slice.

Click Detect.

The selection is highlighted to identify the slices of the M1D table format. Figure 71: Cells selection

7. Update the plot in the right-hand pane.

Figure 72: Plot preview of the table

Once you have made the selection, you can save the table to a file.

Using Data Import you can create look-up tables in the appropriate format to use in components.