30P30N
Multi-element high-lift airfoil.

A demanding three-element high-lift benchmark meshed with RobustMesh and exported directly to OpenFOAM for a k–ω SST RANS simulation.

NARROW GAPS · WALL-RESOLVED · SEPARATION & RECIRCULATION · STEADY INCOMPRESSIBLE AERODYNAMICS

Mesh

310,484 cells

Prismatic layer

30 layers

First prismatic cell height

5 × 10⁻⁶ m

Expansion ratio

1.18

Near-wall target

y⁺ ~ 1

Core mesh type

Triangle

01 / 30P30N geometry

This study considers the 30P30N airfoil in its extended high-lift configuration at an angle of attack of 0°. All dimensions are normalised by a reference chord c_ref = 1 m, defined for the airfoil in its retracted configuration.

Extended 30P30N geometry with slat, main element and flap — ConfigurationExtended

Angle of attack0°

Reference chord1 m · retracted configuration

02 / Mesh composition and spatial resolution

The final mesh combines three nested refinement zones with 30 prismatic layers along the slat, main element and flap. The first prismatic cell is 5 × 10⁻⁶ m thick and the layers use an expansion ratio of 1.18, targeting y⁺ ~ 1. The rest of the domain is discretised with a graded triangular core.

Prismatic layers 213,134

Prismatic cells · 30 layers over the three-element geometry

Core region 97,350

Triangular cells · graded from the near field to the prismatic cells

Exported mesh 310,484

Total cells

Mesh images

Overall final mesh around the slat, main element and flap — **30P30N mesh overview**

Mesh detail in the gap between the slat and main element — **Slat / main-element gap**Prismatic layers and triangular core

Mesh detail in the gap between the main element and flap — **Main-element / flap gap**Gap refinement and layer transition

Mesh detail around the 90-degree corner of the main-element cove — **90° main-element corner**Cove corner at x ≈ 0.700 m

03 / Mesh quality

The cell-quality values and distributions below are taken from the OpenFOAM checkMesh report for the final mesh.

Angular quality

Non-orthogonality

Min0.0000°

Mean5.6203°

Max59.4491°

78.55%

0°–10° 402,631

17.21%

10°–20° 88,217

3.93%

20°–30° 20,126

0.31%

30°–50° 1,592

0.0004%

50°–60° 2

Cell distortion

Skewness

Min0.0000

Mean0.0513

Max2.4998

99.14%

0–0.25 508,155

0.85%

0.25–0.5 4,365

0.01%

0.5–1 27

0.001%

1–2 4

0.003%

2–2.5 17

Cell stretching

Aspect ratio

Min1.0000

Mean3.3707

Max199.1033

89.49%

1–5 277,837

4.95%

5–10 15,355

3.63%

10–25 11,276

1.61%

25–100 5,008

0.32%

100–200 1,008

Interpolation quality

Face weight

Min0.0185

Mean0.5078

Max0.8564

0.02%

0.0185–0.05 92

0.01%

0.05–0.1 75

0.03%

0.1–0.2 139

0.30%

0.2–0.4 1,530

99.64%

0.4–0.86 510,732

04 / Simulation results

The completed steady k–ω SST RANS calculation at Re = 5 × 10⁶, run with simpleFoam from OpenFOAM v2406 over 2,000 iterations, confirms the near-wall resolution across all three elements.

Simulation diagnostics

Convergence and near-wall diagnostics

Convergence

Solver residuals over 2,000 iterations

Iterations Normalised residuals

Uₓ final · 3.57e-6

Uᵧ final · 5.35e-5

p final · 5.90e-6

ω final · 8.75e-9

k final · 7.92e-7

Wall resolution

y⁺ distribution at iteration 2,000

Min0.0043

Mean0.4156

Max1.4134

7.06%

0.00–0.10 227

17.44%

0.10–0.25 561

30.32%

0.25–0.50 975

38.87%

0.50–0.75 1,250

4.88%

0.75–1.00 157

1.43%

1.00–1.50 46

Main element

Min0.004311

Mean0.426

Max1.413

Flap

Min0.01468

Mean0.356

Max1.066

Slat

Min0.02082

Mean0.476

Max0.797

Law of the wall

U⁺ vs y⁺ at iteration 2,000

u_τ0.0532

Sample pointx = 0.751

y⁺ U⁺

Simulated profile

U⁺ = y⁺viscous sublayer

U⁺ = ln(y⁺)/κ + Bcanonical log-law reference

Flow solution

Pressure and velocity fields

Pressure-coefficient field around the 30P30N airfoil averaged over iterations 1,001 to 2,000 — Pressure coefficient **C_p field · mean over iterations 1,001–2,000**

Velocity-magnitude field around the 30P30N airfoil averaged over iterations 1,001 to 2,000 — Velocity magnitude **|U| field · mean over iterations 1,001–2,000**

Experimental validation

Aerodynamic coefficients

Coefficient	Experiment	RobustMesh + OpenFOAM 2406	Percent Error (%)
C_lLift coefficient	2.167¹	2.195²	+1.3%
C_dDrag coefficient	0.0332¹	0.0347²	+4.5%

05 / Files

All RobustMesh configuration files, the complete OpenFOAM v2406 case, the generated mesh, and the simulation results can be downloaded here.