What mesh quality parameters are important in CFD analysis?

Key mesh quality metrics: (1) Skewness: deviation from ideal element shape (target < 0.85, ideal < 0.5). (2) Aspect ratio: longest to shortest edge ratio (target < 5:1 for tets, can be higher for boundary layers). (3) Orthogonality: angle between face normal and line connecting cell centers (target > 0.1, ideal > 0.3). (4) Smoothness: gradual size transition between adjacent cells (growth rate < 1.2). (5) Y+ value: dimensionless wall distance for turbulence modeling (y+ ≈ 1 for resolving viscous sublayer, y+ > 30 for wall functions). Poor mesh quality causes convergence issues, numerical diffusion, and inaccurate results.