Study of Composite Pressure Vessel using Workbench and

APDL

Andrés Liberatto

Eduardo Araujo

PRESENTATION TOPICS

• Motivation

• Geometry – simplification

• Modeling

– Choice of elements

– Meshing Strategy

– Lay-up Definition and Element Orientation

– Boundary Conditions

• Post Processing

• This study was performed with the company CENIC and present the

modeling sequence of a typical pressure vessel fabricated with filament

winding process.

• Geometry, data material were provided by CENIC.

• To use the resources available in Ansys 14.0 Workbench and APDL

Motivation

CENIC

– Step geometry file was provided

– Ansys imports step file

Geometry

• Some components were neglected for this study

– Fasteners

– Anchoring Holes

– Coupling Rings

– O-rings

• All other components were divided (cut) to allow the user to use good

meshing strategy.

– To divide by 4 parts in longitudinal directon

– To divide by 3 parts in transversal direction

• Sweep mesh. At least 2 elements through thickness

– Only brick element. Transition elements are wedges.

Geometry - simplification

• Why should one use bricks?

• Composites (laminated) elements demand

controlled mesh and brick solid elements.

Geometry - simplification

Geometry – after simplification

Modeling- Element Choice

• Ansys 14.0

• Standard resources of Workbench plus APDL

Modeling – Meshing strategy

• Brick and wedge element mesh

– Swept mesh (revolution) around main cylinder axis

– Two elements through thickness to guarantee quality of results

– Named_Selection were used to define the mesh generation regions (vide

images)

– Lay-up is divide by 2 (half for each element)

– Important: laminate thickness will be correct even if there is thickness variation

(domes region). Thickness distribution of layers is proportional to the specified

lay-up.

Modeling – Meshing strategy

Mesh

Mesh – External Cover

Mesh – filament winding vessel

Mesh – Metallic Vessel

Mesh – Metallic Vessel

Mesh – 2 elements through thickness

Named Selections Regions

Named Selections Regions

Named Selections Regions

Named Selections Regions

Named Selections Regions

• APDL (Ansys Parametric Design Language) Commands were used to

define lay-up and Element Orientation

• Domes were divide in 3 transversal parts to accomodate orientation

changes with the capabilities available.

• Ansys Workbench and APDL commands were used to model the pressure

vessel in this presentation . The job would be much easier and simplified

with ACP (Ansys Composite Pre-Post) .

Lay-up Definition and Element Orientation

• Typical APDL commands

Lay-up Definition and Element Orientation

Lay-up Definition and Element Orientation

Lay-up Definition and Element Orientation

Lay-up Definition and Element Orientation

Boundary Condition

Fixed Support

Boundary Condition

Pressure

Boundary Condition

Pressure (internal)

Typical Results

Displacements

von Mises stress (metal)

Typical Results

Typical Results

Von Mises Stress (Metal)

Typical Results

• Results visualization in the layers is done using

APDL commands

Typical APDL

commands

Typical Results

Tensão Equivalente Von Mises

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

Typical Results

OBRIGADO!!

THANK YOU