Week - 4 - 2D meshing for Plastic components

Working: • The easiest and most common method to produce the Bottle cap is Injection
Moulding. • Injection Moulding is the process for producing parts by injecting molten material into
a mold, or mold. Injection moulding can be performed with a host of materials mainly including metals (known as die-casting), glasses, elastomers, confections, and most
commonly thermoplastic and thermosetting polymers. • Material for the part is fed into a heated barrel, mixed, and injected into a mold cavity,
where it cools and hardens to the configuration of the cavity. • Injection moulding is widely used for manufacturing a variety of parts, from the
smallest components to entire body panels of cars. • Advances in 3D printing technology, using photopolymers that do not melt during the
injection moulding of some lower temperature thermoplastics, can be used for some simple injection molds.

Generation of Mid Surface, Mesh of the Bottle Cap
Aim: To create a Mid-Surface and mesh with the given quality criteria and to make sure the element given is free from geometrical errors.
Methodology: The methodology for the given element is as follows:
1. Perform a Geometrical Check (if Errors present fix them) 2. Extraction of Mid surface 3. Assigning Thickness to Mid surface. 4. Giving the Quality Criteria. 5. Creating a mesh 6. Adding thickness to the meshed element.

Given Model: The Model given is the Bottle Cap. The quality Criteria is as below S. No. Quality Criteria
Value Target/ Average Length 1 Minimum Length
0.5 Maximum Length
-
N
w
A
Aspect Ratio
0
Warping
15
0
Skewness
45
1
Jacobian
0.7
0
45
0
Minimum Quad Angle Maximum Quad Angle Minimum Tria Angle
135
ŏ
30
Theory:
1. ANSA (Automatic Net generation for Structural Analysis):
ANSA is a computer-aided engineering tool for Finite Element Analysis and CFD Analysis widely used in the automotive industry. It is developed by BETA CAE Systems. ANSA maintains the association between CAD geometry and the Finite Element (FE) mesh. This means that the FE meshes are better representations of their geometric parents. Also, it is easy to maintain and update any changes in the geometry by simply reworking the updated area instead of recreating the FE from scratch. It carries several proprietary algorithms for meshing suitable for both CFD and structural models.
The software takes a shell material to the solid geometry and converts it into the finite2. Bottle Cap:
• A bottle cap or bottle top seals the top opening of a bottle. • A cap is typically colorfully decorated with the logo of the brand of beverage. • Plastic caps are used for plastic bottles, while metal with plastic backing is used for
glass; the metal is usually steel. • Plastic caps may have a pour spout. Flip-Top caps like Flapper closures provide
controlled dispensing of dry products. • Caps for plastic bottles are often made of a different type of plastic from the bottle. elements so that the model can get accurate simulation results in a shorter time.

result:the quality mesh is obtained with quality criteria

Learning Outcomes:
The Basics of ANSA can be learned by practicing in this model. The following outcomes are learned
• Geometric Clean-up. • Topological Correcting. • Creating of Mid Surface using Offset, Middle, Middle (Multi), and Middle( Curves). • Creating the Mesh. • Correction of mesh errors. • Adding the Thickness.