Meshing 2D shell elements using Hypermesh

Objective:

• To Carry out the geometry cleanup operation on the given 3 models.
• To create the 2D mesh for the given target length and to assign the thickness.

Introduction:

CAE is a process used to verify or simulate through computers instead of manually tesing it by proto-type.CAE tools are very widely used in the automotive industry. In fact, their use has enabled the automakers to reduce product development cost and time while improving the safety, comfort, and durability of the vehicles they produce.Computer-aided engineering (CAE) is the broad usage of Computer software to aid in engineering analysis tasks. It includes (FEA),(CFD), (MBD), durability and optimization.

2-D Shell elements:

These elements are suitable for the 2-D analysis such as plane stress and plane strain. These are also known as the plane elements. Commonly used 2-D elements are the triangular elements and quadrilateral elements. The three noded triangular elements are the first 2-D element used in two-dimensional analysis. These three noded triangular elements are known as the constant strain triangular or linear displacement triangular element because the displacement over these elemnts is linear in nature.

Also, the triangular elements can have six nodes. These six noded triangular elements are known as linear strain triangular or quadratic displacement triangular elements because the displacement variation over these element is parabolic or non linear in nature.

Procedure:

Intially geomtry cleanup was made using the toggle edge, replace node.

Geomtry ===> Quick edit.

After geomtry clean up mid surface was been extracted using the option.

Geomtry===> Mid surface.

To neglect the holes less than 5 mm pinholes delete option was used and neglected the holes

Geomtry===> Defeature===> pinholes===> dia less than 5 mm.

Using the 2D automesh, meshed the models.

2D===>Automesh===>Select the surface.

Even used ruled option for meshing to keep the nodes in the path.

2D===>Ruled===>Select the surface.

Quality checks was assigned using the

Tools===>check elems.

Thickness was assigned and the mesh was moved

The mesh was moved tto the original component.

Quality criteria:

Warpage:

It is defined as the angle b/w the normals to two planes formed by splitting the quad element along the diagonals.The max angle of the two possible angles is reported as the warp angle.

Jacobian:

This measures the deviation of an element from its ideal shape such as a traingles deviation from equilateral.

Skewness:

Skew of triangular elements is calculated by finding the min angle b/w the vector from each node to the opposing mid side and the vector b/w the two adjacent mid-sides at each node of the element .

Images of the models are shown below:

Model 1:

Model 2:

Model 3:

Conclusion:

Mid surface was created and meshed fro the given models.

Quality crieria was sartisfied and assigned the thickness.