SimScale Mesh Parameters Explained

 Here's a breakdown of the additional mesh parameters you mentioned in SimScale, along with explanations and guidance on when to use them:

Algorithm:

• This defines the mesh generation method used by SimScale. Common choices include:
  • Sweeping: Efficient for simple geometries with repetitive features.
  • Octree: Well-suited for complex geometries, but can be computationally expensive for very intricate models.
  • Advanced options: SimScale might offer additional algorithms like Boundary Mesh Refinement for specific needs.
• Choose the algorithm based on your geometry complexity and desired balance between efficiency and accuracy.

Sizing:

This category encompasses several parameters related to element size control:

• Global Mesh Size: Sets the target size for elements throughout the domain.
• Refinement Regions: Define areas for finer mesh resolution.
• Surface Mesh Size: Controls element size specifically on surfaces.
• Minimum and Maximum Cell Size: Set limits on element size for a balanced mesh.
• Growth Rate: Defines how element size changes moving away from refinements.

Fineness:

Fineness refers to the overall density of the mesh, directly related to element size. A finer mesh leads to higher accuracy but requires more computational resources. Use a balance between fineness and efficiency based on your desired accuracy level.

Curvature:

This parameter allows you to refine the mesh based on the curvature of your geometry. A finer mesh is applied near areas with high curvature (e.g., corners, edges) to capture geometric details more accurately.

Automatic Boundary Layers:

This feature automatically generates prismatic cells near walls to capture the boundary layer, a critical region for fluid flow simulations. It's highly recommended to enable this for most CFD simulations.

Physics-Based Meshing:

This advanced option tailors the mesh to specific physical phenomena being simulated. It might consider factors like flow direction or turbulence characteristics to optimize mesh quality for the chosen physics. Use this when standard meshing might not be ideal for capturing the relevant physics accurately.

Hex Element Core:

This setting attempts to create a core region of hexahedral elements within your mesh. Hexahedral elements are generally more efficient than tetrahedral elements, but their suitability depends on your geometry. Use this option for simpler geometries where hexahedral elements can be effectively generated.

Number of Processors:

Similar to simulation control, this controls the number of processors used for mesh generation. More processors can speed up the process, especially for complex geometries, but come at an increased cost.

Maximum Meshing Runtime:

This acts as a safety measure to prevent excessively long mesh generation times. Set this based on your estimated meshing time and resource limitations.

Advanced Settings:

• Small Feature Suppression: Suppresses very small features in the geometry that might not be relevant to the simulation and can negatively impact mesh quality. Use this cautiously, ensuring you don't suppress features crucial for the physics.
• Gap Refinement Factor: Refines the mesh in gaps between geometric parts to capture interactions accurately. Use this when simulating flow between closely spaced components.
• Global Gradation Rate: Controls the overall rate of element size change throughout the domain. Use a smooth gradation rate to avoid abrupt jumps in element size and maintain good mesh quality.

When to Use These Parameters:

• Use curvature, refinement regions, and surface mesh size refinement when specific areas of your geometry require higher mesh resolution.
• Consider physics-based meshing when the standard approach might not be ideal for capturing the relevant physics of your simulation.
• Use the hex element core for simpler geometries where it can be effectively generated for improved efficiency.
• Utilize more processors for mesh generation on complex geometries when computational resources allow.
• Set the maximum meshing runtime to manage resource usage and prevent unexpected delays.
• Apply advanced settings cautiously, understanding their impact on mesh quality and considering the specific needs of your simulation.

Remember, the best approach often involves a combination of these parameters. Consult SimScale's documentation or support for specific recommendations based on your project and meshing goals.

Mesh Parameters in SimScale

Meshing plays a crucial role in CFD simulations. SimScale offers various mesh parameters to control the discretization of your geometry, influencing accuracy, convergence, and computational efficiency. Here's a breakdown of some key mesh parameters:

• Element Type: This defines the fundamental building blocks of your mesh. Common choices include:

  • Tetrahedral: Versatile elements for complex geometries, but can be less efficient than hexahedral elements.
  • Hexahedral: Preferred for simpler geometries due to their higher accuracy and efficiency.
  • Prismatic: Used near boundaries to improve mesh quality and capture boundary layer effects.

• Global Mesh Size: This sets the target size for elements throughout the entire domain. A smaller size creates a finer mesh, leading to higher accuracy but requiring more computational resources.

• Refinement Regions: You can define specific areas within your geometry where a finer mesh is needed to capture high-resolution details (e.g., near corners, surfaces with high curvature).

• Surface Mesh Size: This controls the element size specifically on the surfaces of your geometry. A finer surface mesh is important for accurately capturing boundary layer effects.

• Minimum and Maximum Cell Size: These parameters set limits on the element size within the entire mesh. This helps ensure a balanced mesh without excessively large or small elements.

• Growth Rate: This defines how the element size gradually changes as you move away from refinement regions. A smooth growth rate helps maintain good mesh quality.

• Inflation Layers: These are especially important for capturing boundary layer effects near walls. You can specify the number of layers, their thickness, and the growth rate between them.

• Advanced Meshing Options: SimScale offers additional options like automatic surface repair, anisotropic meshing (adapting element size based on flow direction), and specific meshing algorithms for complex geometries.

Choosing the Right Settings

The optimal mesh parameters depend on your simulation type, geometry complexity, and desired accuracy. SimScale provides defaults, but you can adjust them for more control. Here are some general tips:

• Start with a coarse mesh and refine it gradually until you achieve a good balance between accuracy and computational cost.
• Use refinement regions to focus mesh resolution on critical areas.
• Ensure a smooth transition between element sizes with appropriate growth rate.
• Pay attention to surface mesh size for capturing boundary layer effects.
• Consult SimScale's documentation or support for specific recommendations based on your project.

Here are some additional resources that you might find helpful:

• SimScale Documentation on Meshing: [SimScale Meshing ON simscale.com]

SimScale Mesh Parameters MeshingAlgorithm Sweeping Octree Boundary Mesh Refinement Geometry Complexity Efficiency Accuracy Sizing Global Mesh Size Refinement Regions Surface Mesh Size Minimum Cell Size Maximum Cell Size Growth Rate Fineness Curvature Automatic Boundary Layers Physics Based Meshing Hex Element Core Processors Maximum Meshing Runtime Advanced Settings Small Feature Suppression Gap Refinement Factor Global Gradation Rate