Stiffened Fuselage Barrel Transverse Bending and Bredt-Batho Torsion
Statics (beam-shell)PASS · 1.46%Cantilever transverse bending (V = 50 kN) and Bredt-Batho torsion (T = 100 kN·m) of an aircraft fuselage section with 96 stringers and 15 frames: tip deflection, crown stress, twist angle, and shear stress verified against composite section Steiner and Bredt-Batho formulas.Cantilever transverse bending (V = 50 kN) and Bredt-Batho torsion (T = 100 kN·m) of an aircraft fuselage section with 96 stringers and 15 frames: tip deflection, crown stress, twist angle, and shear stress verified against composite section Steiner and Bredt-B… show full text
- Tolerance:
- 5%
Problem statement
- Geometry
- Cylindrical fuselage barrel R = 1.95 m, L = 7.0 m, skin t = 1.8 mm reinforced by 96 tee stringers (36×1.6, h=24) and 15 I-beam frames (90×30×2×2.5 mm, spacing 0.5 m). Steiner composite section inertia I_eff = 5.8875e-2 m⁴ (+40% stiffening from stringers).
- Material
- Aluminum alloy: E = 72 GPa, ν = 0.33, G = 27.068 GPa, ρ = 2780 kg/m³.
- Boundary conditions
- Fully clamped at root ring x = 0 (all 6 DOFs). Load cases: 1) Downward transverse shear force V = 50 kN distributed along tip stringer lines as q = V·cos(φ)/(πR); 2) Torque T = 100 kN·m applied as uniform tangential shear flow q = T/(2πR²).
- Measured quantity
Transverse bending tip deflection: reference 2.5212 mm (bending 1.349 + shear 1.173 mm), computed 2.4845 mm (1.46% deviation). Crown axial stress: reference 9.624 MPa, computed 9.560 MPa (0.67%). Torsion Bredt-Batho twist angle: reference 0.30838 mrad, computed 0.30664 mrad (0.56%). Skin shear stress: reference 2.3253… show full text
Transverse bending tip deflection: reference 2.5212 mm (bending 1.349 + shear 1.173 mm), computed 2.4845 mm (1.46% deviation). Crown axial stress: reference 9.624 MPa, computed 9.560 MPa (0.67%). Torsion Bredt-Batho twist angle: reference 0.30838 mrad, computed 0.30664 mrad (0.56%). Skin shear stress: reference 2.3253 MPa, computed 2.3276 MPa (0.10%).
WebCAE Terminal
Paste these commands into the Terminal panel inside WebCAE. They use the same text DSL as the application; run one command per line:
units m
material E=72e9 nu=0.33 density=2780
frame up=z
frame patch geom=cyl o=0,0,0 axis=1,0,0 ref=0,0,1 r=1.95 a0=0 a1=360 len=7 nu=192 nv=56 t=0.0018
frame stiffen patch=1 i="0:191:2" section=tee d1=0.024 d2=0.036 d3=0.0016 d4=0.0016 flush=inner
frame stiffen patch=1 j="0:55:4" section=ibeam d1=0.09 d2=0.03 d3=0.002 d4=0.0025 flush=inner
frame support patch=1 side=i0 dofs=all
frame load node=10945 force=0,0,-50000
frame solve static
frame probe disp node=10945 comp=uz id="tip_w"Results comparison
| Reference value | 2.5212 mm (tip w), 9.624 MPa (crown sigma), 0.30838 mrad (twist), 2.3253 MPa (tau) |
| Our result | 2.4845 mm (tip w, 1.46%), 9.560 MPa (crown, 0.67%), 0.30664 mrad (twist, 0.56%), 2.3276 MPa (tau, 0.10%) |
| Deviation | 1.46% |
| Tolerance | 5% |
| Status | PASS · 1.46% |
| Element family | Beam + Shell |
| Mesh details | 16240 shell quad + beam stiffeners (frame patch + frame stiffen), 16353 nodes, 8861 beams, 98118 DOFs; webcae_solve |
Updated: 2026-10-19 · WebCAE solver