# Meshing Settings

Comprehensive guide to Flow360's meshing capabilities, covering default parameters, volume zones, and refinement techniques for optimal CFD simulations.

# 📋 Available Options

Component Description
Meshing Defaults Fundamental control parameters for mesh generation
Volume Zones Specialized regions for specific flow features
Refinements Local mesh control for critical regions

# 🔍 Detailed Descriptions

# Meshing Defaults

Core parameters controlling the fundamental aspects of mesh generation.

  • Surface mesh characteristics
  • Boundary layer properties
  • Global refinement levels
  • Gap treatment strategies

# Volume Zones

Specialized regions for specific flow applications.

  • Farfield zones for external flow simulations
  • Rotation cylinder zones for rotating machinery
  • Custom volume zones for specific flow features

# Refinements

Local mesh control mechanisms for critical regions.

  • Surface edge refinements
  • Boundary layer refinements
  • Uniform refinements
  • Axisymmetric refinements
  • Passive spacing controls

💡 Tips
  • Begin with default settings and adjust based on specific needs
  • Use refinement regions strategically for critical flow features
  • Consider using passive spacing for interface regions
  • Monitor solution convergence when adjusting mesh parameters
  • Validate mesh quality metrics before proceeding with simulation
  • Start with coarser meshes and refine based on solution quality
  • Ensure smooth transitions between different mesh regions
  • Consider computational resources when setting refinement levels

Common Pitfalls
  • Over-refinement in non-critical regions
  • Insufficient wake resolution
  • Poor boundary layer transition
  • Inadequate gap treatment
  • Inconsistent refinement levels

Meshing Considerations

  1. Surface Mesh Quality

    • Maintain element quality metrics
    • Ensure proper resolution of geometric features
    • Consider curvature-based refinement

  2. Boundary Layer Resolution

    • Target appropriate y+ values
    • Use suitable growth rates (typically 1.1-1.2)
    • Ensure sufficient layers for boundary layer development

  3. Wake and Off-Body Features

    • Extend refinement regions appropriately
    • Consider flow angles and operating conditions
    • Account for expected flow features

❓ Frequently Asked Questions

  • How do I determine appropriate refinement levels?

    Start with default settings and adjust based on flow features and geometric complexity. Use refinement regions for critical areas and monitor solution quality.

  • What's the best approach for rotating machinery?

    Combine boundary layer refinement with axisymmetric refinement, ensuring proper resolution of tip vortices and wake regions.

  • When should I use different volume zone types?

    Use farfield zones for external flows, rotation cylinders for rotating machinery, and custom zones for specific flow features requiring specialized treatment.

🐍 Python Example Usage

 
from flow360 import (
    MeshingParams,
    MeshingDefaults,
    AutomatedFarfield,
    RotationCylinder,
    SurfaceRefinement,
    BoundaryLayer,
    u
)

# Configure meshing parameters
meshing_params = MeshingParams(
    defaults=MeshingDefaults(
        surface_edge_growth_rate=1.2,
        surface_max_edge_length=0.1 * u.m,
        boundary_layer_growth_rate=1.2,
        boundary_layer_first_layer_thickness=0.01 * u.mm
    ),
    volume_zones=[
        AutomatedFarfield(method="auto"),
        RotationCylinder(
            spacing_axial=0.02 * u.m,
            spacing_radial=0.01 * u.m,
            spacing_circumferential=0.015 * u.m,
            entities=[propeller_cylinder]
        )
    ],
    refinements=[
        SurfaceRefinement(
            name="wing_surface",
            faces=[left_wing_surface],
            max_edge_length=0.05 * u.m
        ),
        BoundaryLayer(
            name="wing_bl",
            faces=[right_wing_surface],
            first_layer_thickness=1e-5 * u.m,
            growth_rate=1.2
        )
    ]
)

← Meshing Defaults →