Home
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.
Reporting Results
Reports provide summaries of solution data.
Statistical Reports
Statistical reports apply statistical functions to scalar data sourced from chosen parts in the simulation.
Mass Averaged

Share

Link: copied

Breadcrumb: copied

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.
- 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.
  - What Is a Report?
    A report presents a computed summary of the current simulation or CPU data. A node represents each report in the simulation tree, each with its own pop-up menu. Report properties, however, vary by report type.
  - System Reports
    System reports provide information related to the running of the simulation.
  - Statistical Reports
    Statistical reports apply statistical functions to scalar data sourced from chosen parts in the simulation.
    - Complex Chemistry Reports
      The Complex Chemistry Reports have their own properties and use a common report pop-up menu.
    - Element Count
      The element count report has its own properties and uses a common report pop-up menu.
    - Frontal Area
      The frontal area report calculates the combined projected area of all parts in the report onto a user-specified plane.
    - Line Integral
      The line integral report is represented in the simulation tree by a node. Right-click this node to access the pop-up menu of the line integral report.
    - Mass Averaged
    - Mass Flow Averaged
    - Maximum
      The maximum value report returns the maximum cell value in the selected regions, the maximum face value in the selected boundaries, or the maximum value of $ϕ$ for each parcel in a Lagrangian phase.
    - Minimum
      The minimum value report returns the minimum cell value in the selected regions, the minimum face value in the selected boundaries, or the minimum value of $ϕ$ for each parcel in a Lagrangian phase.
    - Monitor Derivative
      The monitor derivative report is a monitor-based report that numerically computes the derivative of one monitor with respect to another as of the latest sample time/iteration that they have in common. This shows how much one monitor is affecting another.
    - Monitor Integral
      The monitor integral report integrates the value of one monitor (the integrand) against the values of another monitor (the variable) using the trapezoidal rule for integration. Only those iterations on which both monitors (integrand and variable) have data are included in the computation.
    - Overset Surface Integral
      This report is particularly useful for overset mesh simulations. It computes the surface integral of a scalar quantity by taking into account the area of the overlapping cells of overlapping regions only once.
    - Overset Volume Integral
      This report is particularly useful for overset mesh simulations. It computes the volume integral of a scalar quantity by taking into account the volume of the overlapping cells of overlapping regions only once.
    - Particle Average
      This report type is available only when the Lagrangian Multiphase model is activated.
    - Statistics Report
      A statistics report allows you to compute statistics from data collected by a report-based monitor. You can compute the mean, sum, maximum, or minimum values of all or some of the data. You can also compute the variance and root mean square metrics for the data.
    - Sum
    - Surface Area Average
      This report type is available only when the Lagrangian Multiphase model is activated.
    - Surface Average
    - Surface Integral
    - Surface Standard Deviation
    - Surface Uniformity
    - Two Monitor Co-temporal Lookup Report
      The two monitor co-temporal lookup report searches for a specified lookup value in a source monitor, finds its first position, and returns the value of a co-temporal monitor at that position. Linear interpolation is used if the location falls between two monitor samples.
    - Two-Monitor Statistics Report
      A two-monitor statistics report allows you to compute the covariance or correlation of two monitors.
    - Volume Average
    - Volume Integral
    - Volume Standard Deviation
    - Volume Uniformity
  - Specific Reports
    Some reports in Simcenter STAR-CCM+ are only available in conjunction with specific physical models. For example, Simcenter STAR-CCM+ can only compute the acceleration of a rigid body if the simulation contains one or more rigid bodies. The reports manager pop-up menu only exposes reports that Simcenter STAR-CCM+ can compute for the current simulation.
  - Expression Report
    The expression report depends on a combination of reports, except for system reports. It works with the field function generated for each report you want to use.
  - Obtaining Statistics from Data in Monitors
    A statistics report allows you to compute statistics from data collected by any monitor that can be plotted, including report monitors, residual monitors, physical time monitors, and the iteration monitor. You can compute the mean, sum, maximum, or minimum values of all or some of the data.
  - Understanding Report Errors
    Error output is available for a subset of commonly used reports—reports that require a field function and a list of parts to be specified by the user.
  - Report Field Functions
    When you create a report, a field function corresponding to that report is added automatically. You can reference this field function in expressions and user-defined field functions.
  - Reporting Additional Field Functions at Maximum or Minimum
    The maximum and minimum reports accept a list of field functions whose values are output at the location of the maximum or minimum value of the primary field function.
  - Using Coordinate Systems with Force and Moment Reports
    Force and moment reports accept a Coordinate System specification that defines the frame of reference for both the Direction property and the computed report value.
  - Using Bands with Force and Moment Reports
    Simcenter STAR-CCM+ can compute force and moment values (in the laboratory coordinate system only) at intermediate band locations across a surface. This computation must be triggered using a Java macro and is not available through the user interface.
  - Working with Parts-Based Interfaces in Reports
    You can report results for parts-based interfaces -- the areas where the surfaces of parts come into contact with each other, or the remainders of those surfaces. Using parts-based interfaces improves performance for simulations that have many parts.
  - Obtaining Whole Domain Reports through Idealizations
    In many engineering simulations, it is common practice to reduce the size of the computational domain using planes of symmetry, axes of rotation (axisymmetry), or periodicity. When you compute reported values, however, you generally want to account for the whole domain in the computation. Using idealizations, Simcenter STAR-CCM+ allows you to compute report values for the full model using only the results for the partial model.
  - Options for Excluding Hydrostatic Pressure from Fluid Loads Calculations
    To simplify comparison between different designs, you have an easy option to exclude the hydrostatic contribution from the force calculation, thereby eliminating any dependency on the reference pressure and/or reference height.
  - Reports Bibliography
- 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.

Mass Averaged

The mass averaged scalar quantity is computed over a volume as:

Figure 1. EQUATION_DISPLAY

M a s s A v e r a g e \equiv \frac{\int_{V} ρ ϕ d V}{\int_{V} ρ d V} = \frac{\sum_{c}^{} ρ_{c} ϕ_{c} V_{c}}{\sum_{c}^{} ρ_{c} V_{c}}

(389)

where $ϕ_{c}$ is the cell value of the selected scalar, $ρ_{c}$ is the cell density and $V_{c}$ is the cell volume.

The mass average over parcels in a Lagrangian phase is computed as:

Figure 2. EQUATION_DISPLAY

M a s s A v e r a g e \equiv \frac{\int_{V} ρ ϕ d V}{\int_{V} ρ d V} = \frac{\sum_{π}^{} ϕ_{p} m_{p} n_{π}}{\sum_{π}^{} m_{p} n_{π}}

(390)

where $m_{p}$ is the mass of a single particle represented by a parcel and $m_{p} n_{π}$ is the mass of the parcel.

See also the properties of this statistical report.

Mass Averaged in Harmonic Balance

When the Harmonic Balance model is selected, the mass averaged scalar quantity over a volume is computed as:

Figure 3. EQUATION_DISPLAY

R = \frac{\sum_{c} {\hat{M}}_{0 c} {\tilde{ϕ}}_{c}}{\sum_{c} {\hat{M}}_{0 c}}

(391)

where:

${\hat{M}}_{0 c} = {\hat{ρ}}_{0 c} {\hat{V}}_{0 c}$ is the time-mean mass at cell $c$ .
${\hat{ρ}}_{0 c}$ is the time-mean density at cell $c$ .
${\hat{V}}_{0 c}$ is the time-mean cell volume of cell $c$ .
${\tilde{ϕ}}_{c} = C \cdot ϕ_{c}^{*}$ is the time-mean scalar at cell $c$ for the Volume Mesh Representation and the specific variant of the scalar requested by the HB Solution View for HB Solution View Representation (for example, Scalar at a specific time instant or Fourier Mode 2 Phase of Scalar).