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Tutorials
Tutorials show you how to use Simcenter STAR-CCM+ for various applications in a step-by-step format with recommendations for setup, initialization and steps of the solution process specific to the application. Macro and simulation files are available for download for a large proportion of cases.
Compressible Flow
The tutorials in this set illustrate various Simcenter STAR-CCM+ features for compressible fluid flows as well as harmonic balance.
Adaptive Mesh Refinement: Hypersonic Flow
Hypersonic flows and flight envelopes present unique challenges in Computational Flow Dynamics. The extreme gradients and shocks can push flow solvers to their limits and resolving the flow features, particularly shock formation, is of paramount importance in obtaining valid converged solutions. In Simcenter STAR-CCM+, you can apply Adaptive Mesh Refinement (AMR) to accurately resolve developing shocks using refinement based on solution gradients.
Setting the Solver Parameters
The simulation runs for 1000 iterations with mesh adaption triggered every 100 iterations. You specify the update frequency in the Adaptive Mesh solver. Additionally, the Coupled Implicit solver requires special settings because of the high-speed hypersonic flow regime. Normally, solver defaults are adequate for most compressible flow cases without requiring any change.

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Tutorials
Tutorials show you how to use Simcenter STAR-CCM+ for various applications in a step-by-step format with recommendations for setup, initialization and steps of the solution process specific to the application. Macro and simulation files are available for download for a large proportion of cases.
- Using Tutorial Macros and Files
  Macros, input files, and final simulation files for a range of tutorials are provided as an optional download package on the Support Center website. These macros and final simulation files are provided as an aid to the written tutorials, so that you can check your final results against the downloaded files, or against a simulation that is built and run using the macros.
- Introduction
  Welcome to the Simcenter STAR-CCM+ introductory tutorial. In this tutorial, you explore the important concepts and workflow. Complete this tutorial before attempting any others.
- Foundation Tutorials
  The foundation tutorials showcase the major features of Simcenter STAR-CCM+ in a series of short tutorials.
- Geometry
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for creating and working with parts and 3D-CAD.
- Mesh
  The tutorials in this set illustrate various STAR-CCM+ features for building CFD meshes.
- Incompressible Flow
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for incompressible fluid flows as well as porosity and solution recording
- Compressible Flow
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for compressible fluid flows as well as harmonic balance.
  - Subsonic Flow: NACA-Type Intake
    This tutorial illustrates how to solve a three-dimensional compressible flow problem using Simcenter STAR-CCM+.
  - Transonic Flow: RAE2822 Airfoil
    The tutorial simulates two-dimensional, turbulent, compressible, transonic air flow over an idealized airfoil.
  - Transonic Flow: RAE2822 Airfoil Using Overset Mesh
    This tutorial demonstrates how to use an overset mesh to simulate transonic flow over the RAE2822 airfoil.
  - Anisotropic Volume Meshing: Onera M6 Wing
    When meshing aerospace geometries such as wings, propeller blades, or turbine blades, you are required to generate a very fine mesh that adequately captures the curvature of the leading and trailing edges. To help reduce the cell count while maintaining solution accuracy, Simcenter STAR-CCM+ provides an anisotropic meshing option by which you can refine these edges.
  - Adaptive Mesh Refinement: Hypersonic Flow
    Hypersonic flows and flight envelopes present unique challenges in Computational Flow Dynamics. The extreme gradients and shocks can push flow solvers to their limits and resolving the flow features, particularly shock formation, is of paramount importance in obtaining valid converged solutions. In Simcenter STAR-CCM+, you can apply Adaptive Mesh Refinement (AMR) to accurately resolve developing shocks using refinement based on solution gradients.
    - Loading the Starting File and Generating the Volume Mesh
      You start this tutorial by loading a simulation file and generating the volume mesh.
    - Setting up Physics Continuum
      In the physics continuum, you choose the Coupled Flow model for solving the steady hypersonic flow. Mesh adaption is activated by choosing the Adaptive Mesh model. In a later stage, you define the adaptive criterion based on the Mach number.
    - Creating a User-Defined Adaptive Mesh Criterion
      After selecting the Adaptive Mesh model in the physics continuum, you define a field function that returns an adaption criterion based on the gradient of the Mach number.
    - Setting Up Boundary and Initial Conditions
      You specify the physics values for the free stream boundary and set the corresponding values to the initial conditions also.
    - Setting the Solver Parameters
      The simulation runs for 1000 iterations with mesh adaption triggered every 100 iterations. You specify the update frequency in the Adaptive Mesh solver. Additionally, the Coupled Implicit solver requires special settings because of the high-speed hypersonic flow regime. Normally, solver defaults are adequate for most compressible flow cases without requiring any change.
    - Visualizing the Mach Number on the Adapted Mesh
      To visualize the shock wave in the hypersonic flow, you create a scalar scene across the region that plots Mach number. As an indicator of mesh adaption you add a cell count annotation within the scalar scene.
    - Running the Simulation
      Here you set up a stopping criterion and run the simulation. As defined in the AMR solver settings, the mesh is adapted every 100 iterations.
  - Harmonic Balance: Single Stage Periodic Flow
    The tutorial illustrates the steps necessary to simulate a single axial compressor blade row so that the effect of a periodic wake can be analyzed using the Harmonic Balance method.
  - Gas Turbine Aerodynamics: Post-Processing
    In turbomachinery studies, the analysis of the flow field throughout the blade passage requires advanced post processing methods.
- Heat Transfer and Radiation
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for heat transfer, radiation, and thermal comfort.
- Multiphase Flow
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for simulating multiphase fluid flow problems
- Discrete Element Method
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for simulating Discrete Element Method problems
- Motion
  The tutorials in this set illustrate various STAR-CCM+ features for simulating problems with moving geometries and meshes, dynamic fluid body interaction, and rigid body motion:
- Reacting Flow
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for simulating reacting flows such as combustion.
- Solid Stress
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for computing deformation, strain, and stresses in solid regions. They also show how such computations can be coupled to the fluid behavior in an analysis of fluid-structure interaction.
- Aeroacoustics
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for solving aeroacoustic simulations.
- Electromagnetism
  The following tutorials illustrate features for solving problems that involve electromagnetic fields.
- Electrochemistry
  The following tutorial demonstrates chemical reactions induced by an electrical current.
- Battery
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for setting up a battery model:
- Automation
  The tutorials in this set illustrate various Simcenter STAR-CCM+ automation and macro features.
- Design Exploration
  The tutorials in this set illustrate various features for running design exploration studies in Design Manager.
- Coupling with CAE Codes
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for coupling with CAE codes:
- Analysis Methods
  The tutorials in this set illustrate various Simcenter STAR-CCM+ features for analysing and visualizing simulation data.
- Simcenter STAR-CCM+ In-cylinder
  The tutorials in this set illustrate features for simulating internal combustion engines in Simcenter STAR-CCM+ using the dedicated add-on Simcenter STAR-CCM+ In-cylinder.

Setting the Solver Parameters

The simulation runs for 1000 iterations with mesh adaption triggered every 100 iterations. You specify the update frequency in the Adaptive Mesh solver. Additionally, the Coupled Implicit solver requires special settings because of the high-speed hypersonic flow regime. Normally, solver defaults are adequate for most compressible flow cases without requiring any change.

To specify the AMR update frequency:

Select the Solvers > Adaptive Mesh > Trigger > Iteration Frequency node and set Iteration Frequency to 100.

According to the residual plot, the flow solution converges by one order of magnitude after 100 iterations. Reaching this level of initial convergence gives a sufficient solution on which to perform the first mesh adaption. Avoid performing mesh adaption on an entirely unconverged solution.

To set up the Coupled Solver for hypersonic flow:

Edit the Solvers > Coupled Implicit node and set the following properties:


Node	Property	Setting
Coupled Implicit	CFL Control Method	Automatic Automatic CFL control adjusts the CFL number in response to the AMG solver convergence behavior so that the specified target number of cycles is maintained. CFL control targets a balance between the cost of forming the linear system and the cost of solving it.
Coupled Implicit	Enhanced Dissipation	✓
AMG Linear Solver	Convergence Tolerance	0.001 For this particular case with hypersonic flow, some benefit is obtained by reducing this parameter. You reduce the tolerance by which residuals of the linear system must be reduced before multigrid cycling stops. A tolerance of 0.001 requires a drop of three orders of magnitude.
AMG Linear Solver	Relaxation Scheme	ILU This relaxation scheme is numerically more appropriate for hypersonic compressible flows than the Gauss Seidel Scheme and promotes faster convergence.
Expert Initialization	Method	Grid Sequencing Grid sequencing performs the normal initialization followed by successive computations for an approximate inviscid solution to the flow problem.
Grid Sequencing	CFL Number	2.5 Gradients for hypersonic flows can be high especially in the solution initialization stage. Lowering the CFL number slows the progress of grid sequencing and reduces the potential for high gradients to cause problems.