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Post-Processing
Simcenter STAR-CCM+ allows you to post-process the solution after each iteration or time-step, (while the simulation is running), as well as when the simulation completes. For this reason, you generally create post-processing objects before running the simulation. Post-processing objects are also known as analysis objects.
Accessing Solution Data through Derived Parts
Although Simcenter STAR-CCM+ can display, analyze, and report simulation data on regions, boundaries, and parts, there are many cases when you want to access data in other entities of the solution space. Derived parts provide a mechanism for defining additional entities on which you can access solution data.
Defining an Isosurface
An isosurface is a surface where the scalar function takes on a constant value. Simcenter STAR-CCM+ allows the creation of an isosurface from parts comprising regions, boundaries, and other parts, however input parts are enforced to be of the same dimensionality.

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Post-Processing
Simcenter STAR-CCM+ allows you to post-process the solution after each iteration or time-step, (while the simulation is running), as well as when the simulation completes. For this reason, you generally create post-processing objects before running the simulation. Post-processing objects are also known as analysis objects.
- Analysis Workflow
  The key steps in successfully analyzing simulation results are to: (1) be clear on what quantities you want to extract; (2) locate or define surfaces on which to obtain the data; and, (3) present the data in visual scenes or numeric output.
- Data Interpolation
  Most visualization objects such as plots, reports, and scalar displayers allow for smooth and non-smooth values. For example, the contour style for scalar displayers provides a Smooth Filled option (smooth) and a Filled option (non-smooth). The way these values are calculated depends on the discretization method.
- Field Function Interpolation and Interfaces (FV)
  For finite volume meshes, understanding how Simcenter STAR-CCM+ deals with field function data is important for avoiding non-physical results in post-processing at an interface, and to appreciate the difference that smoothing makes when it is applied.
- Accessing Solution Data through Derived Parts
  Although Simcenter STAR-CCM+ can display, analyze, and report simulation data on regions, boundaries, and parts, there are many cases when you want to access data in other entities of the solution space. Derived parts provide a mechanism for defining additional entities on which you can access solution data.
  - Defining Derived Parts: General Workflow
    Derived parts are contained within their own node in the simulation tree; you create them using the context menu on that node. When a graphics scene is open at the same time, Simcenter STAR-CCM+ provides an edit dialog and activates an interactive placement tool in the scene.
  - Using the Visual Tools
    Included in Simcenter STAR-CCM+ are tools that let you manipulate derived parts visually.
  - Reading an External File
    An arbitrary section, arbitrary probe, or constrained plane section can read data from an external file (STL or VTK).
  - Exporting to an External File
    You can export the data of derived parts to an external file in STL or VTK format.
  - Splitting Derived Parts by Input and by Value
    When visualizing or reporting you may want to understand the contributions of an individual part that intersects with a derived part. Alternatively, you may want to analyze the values of individual sub-parts of a derived part. To do this, Simcenter STAR-CCM+ lets you split a derived part.
  - Calculating the Surface Area of a Part
    When a volume representation is active, the surface area of a part such as a plane section, a cylinder surface, a sphere, or even an isosurface can be calculated using a surface integral report with a value of 1.
  - Defining Implicit Sections
    Implicit sections are derived parts that are based on planes or geometrical shapes, which can cut through one or more volumes or surfaces.
  - Defining an Isosurface
    An isosurface is a surface where the scalar function takes on a constant value. Simcenter STAR-CCM+ allows the creation of an isosurface from parts comprising regions, boundaries, and other parts, however input parts are enforced to be of the same dimensionality.
  - Defining a Threshold
    The threshold part isolates a group of cells based on their relationship to specified scalar values. Simcenter STAR-CCM+ allows the creation of a threshold part from one or more parent parts, provided the set of parent parts are of the same dimensionality.
  - Defining a Scalar Warp Surface
    The scalar warp surface moves the point coordinates on the surface of its input parts along the point normal vectors by an amount equal to the scalar value times the scale factor.
  - Defining a Vector Warp Surface
    A vector warp surface is a part that modifies input surface point coordinates by moving points along the selected vector multiplied by the scale factor.
  - Defining a Streamline
    A streamline part represents particle paths, computed from a vector field. Simcenter STAR-CCM+ offers two types of streamline parts: streamlines and constrained streamlines. Constrained streamlines are particle paths that are constrained to lie in a surface, and can be used to simulate effects such as oil streaks.
  - Defining an (m',theta) Warp
    In Simcenter STAR-CCM+, the (m', theta) warp is used to present a flattened surface of revolution.
  - Defining a Separation/Attachment Line
    Separation/attachment lines are lines along which flow separates from or attaches to a surface.
  - Defining a Vortex Core Part
    In Simcenter STAR-CCM+, the vortex core part automatically extracts vortex cores in a flow field.
  - Defining an Average Surface (Turbomachinery)
    In Simcenter STAR-CCM+, the average surface part evaluates the average or weighted average of a chosen scalar or vector field function over a 3D region or part in the context of an axisymmetric parameterization. This derived part is typically used for post-processing results of a turbomachinery analysis.
  - Defining an Average Profile (Turbomachinery)
    In Simcenter STAR-CCM+, the average profile part evaluates the averages of fields from the input surfaces into discrete bins using the parameters that the axisymmetric parameterization computes. It provides a projected profile of circumferentially-averaged values based on the field values of the input surfaces of revolution (such as isosurfaces and plane sections). This derived part is typically used for post-processing results of a turbomachinery analysis.
  - Defining a Subdivision Part
    To improve visualization of finite element-based field functions, for example those arising in electromagnetics, you can subdivide the mesh.
  - Defining Probes
    This section explains the derived parts that take samples of data in a region based on coordinates or intervals that you specify.
  - Defining a Cell Surface
    The cell surface part represents all the cells adjacent to or intersected by a given part.
  - Defining a Resampled Volume
    Volume rendering is used to display (semitransparent) volumetric objects that are defined in a 3D domain. If your graphics card does not support volume rendering, activate advanced rendering for the relevant scene.
  - Derived Parts Reference
  - Derived Parts Bibliography
- Visualizing the Solution
  The visualization tools in Simcenter STAR-CCM+ are integrated with the analysis, allowing for the interactive extraction and viewing of solution data from either a running or converged simulation.
- Transient Solution Data
  For transient solutions, Simcenter STAR-CCM+ provides the simulation history file (.simh) to which you can save selected data while a simulation is running. After the simulation completes, you can load this file and query its states for post-processing.
- Sampling Data Values Using Reports and Monitors
  This workflow incorporates the roles of both reports and monitors.
- Accessing Field Data from Previous Time-Steps or Iterations
  A field history is a type of field monitor that stores a finite number of past values (or samples) of a field function, captured at moments defined by its update policy, for a given set of input regions or boundaries (or both).
- Reporting Results
  Reports provide summaries of solution data.
- Monitoring the Solution
  Monitors sample, save, and plot solution data.
- Plots
  The plotting features in Simcenter STAR-CCM+ allow you to create three kinds of two-dimensional plots.
- Exploring Solutions with Data Focus
  This interactive tool lets you extract knowledge of merit -- information that facilitates a correct engineering decision -- from a large volume of data.
- Parametric Positioning for Analysis Surfaces in Turbomachine Domains
  In studies of cases of revolving volumes, such as turbomachinery, a typical requirement for post-processing is to render and plot data on surfaces or profiles that are positioned parametrically in relation to the domain bounding surfaces. For example, you may wish to view the total pressure on a surface located exactly half-way between the hub and shroud, or you may wish to plot pressure across both blade surfaces on a given slice.
- Triggers and Update Events
  Several features of Simcenter STAR-CCM+ require that you define a trigger for when an action takes place. Simcenter STAR-CCM+ provides three built-in trigger types, and one custom trigger type (defined by an update event).
- Signal Processing
  Signal processing applies data set functions to sets of wave data.

Defining an Isosurface

An isosurface is a surface where the scalar function takes on a constant value. Simcenter STAR-CCM+ allows the creation of an isosurface from parts comprising regions, boundaries, and other parts, however input parts are enforced to be of the same dimensionality.

The exact form of the output of the isosurface depends on the dimensionality of the input parts. Input data consisting of three-dimensional cells result in output isosurfaces, input data consisting of two-dimensional cells result in iso lines, and input data consisting of one-dimensional data result in points.

To create an isosurface:

Follow the general procedure outlined in the section, Defining Derived Parts General Workflow. Choose the menu option, New Part > Isosurface....
Specify the input parts and display option as described in the section, Defining Derived Parts General Workflow.
Complete the isosurface definition by specifying the following properties:
- Scalar field — select the scalar field function as the basis for the isosurface. The list of available scalar field functions depends on the physics models that you selected.
  You can specify the scalar field in the Scalar Field property, or the Scalar group box in the in-place dialog.
- Mode — specify single or multiple isosurfaces, or a closed isosurface.
  You can specify the mode in the Mode property, or the Extraction Mode box in the in-place dialog.
- Isovalues — specify a single scalar value for a single isosurface, a range of scalar values for multiple (range) isosurfaces, or a list of scalar values for multiple (arbitrary) isosurfaces.
  You can specify the scalar values in the in-place dialog, or in the properties of the isosurface child nodes. Click Query to select a scalar range automatically.
- Number of isosurfaces — For multiple isosurfaces, specify the number of isosurfaces that you want to define.
For more information on the available properties, see Isosurface Properties.

Once you have finished the creation process, rotate and zoom in the display to get a clear view of the isosurface. If you did not assign the part to the current scene, you can drag and drop its node into the visualization display. You can show a smooth surface by activating the Smooth Shade property of the geometry displayer.