SOL ALPHA
Pressure vessels · Vessel nozzle

Assess a nozzle-to-shell junction with FELV and FEA

Verify local stresses at a complex nozzle-to-shell junction using analytical screening and a FELV finite-element model.

5 solution steps5 suggested modulesStatus: solution concept

The engineering task

A large or unusual nozzle is loaded by internal pressure, piping forces and moments. Nearby openings, reinforcement pads, thickness transitions or adjacent attachments lie outside the reliable scope of simple formulae. A traceable stress assessment using a three-dimensional finite-element model is required.

An FEA result is meaningful only when loads, boundary conditions, mesh, stress classification and allowable limits follow the selected code. Singularities at sharp edges must not be treated as physical structural stress; membrane, bending and peak components require separation according to the assessment route.

Required design data

  • Final nozzle, shell and weld geometry
  • Pressure, temperature and piping load cases with coordinates
  • Material properties and allowable stresses
  • Code, stress categories and acceptance criteria

Technical solution approach

Perform analytical screening

Estimate opening reinforcement and local loads where possible to establish FEA plausibility targets.

Define model boundaries

Adequate shell extent, realistic symmetry, supports and load application prevent artificial boundary stress.

Build the FELV model

Transfer geometry, contacts, materials, load combinations and locally refined mesh reproducibly to COMSOL.

Check convergence and stresses

Review mesh convergence, deformation and linearised stress along defined classification lines.

Complete checks and variants

Assess plastic collapse, local failure and any fatigue criteria, then compare design variants.

Expected deliverables

Documented finite-element model
Mesh and boundary-condition verification
Classified stresses by load case
Utilisations and design recommendation

Suitable SOL ALPHA modules

The modules form a technically plausible toolchain. Their final selection and sequence will be confirmed during the later calculation against the applicable code and project conditions.