Week 6- Challenge
Objective : 1) To generate mid surface and geometry cleanup of component.
2) To generate mesh over given component.
3) To check the quality papameters of given component.
CAD file:
CAD File contains varius different components as shown below
1) Inner Panel:
2) Outer Panel
3) hinge reinforcement extract body 1 and body 2
5) Latch reinforcement extract body 1
Procedure:
1) To generate mid surface of components.
While working on component we got to know that it contains soild surface , as we don’t require solid surface in 2D meshing we can delete the solids from the components.
To generate mid surface in Automesh panel change the extraction option from offset +plane+sweep to skin offset as the given model is of sheet metal we require very good and accurate mid surface.
As we have restriction to generate element we have to trim the inner surface in half.
2) To clean up geometry and generating mesh.
Before cleaning the surface we have to specify edit parameter and edit criteria. While edit parameter deals with geometry cleanup and edit criteria deals with element quality the element criteria are pre determined in problem statement.
Quality parameters are as follows.
As the given geometry is of complex shape and we have to generate quad dominating mesh we will use mixed type mesh and keeping the size of element as 5. Also to capture whole surface properly we have to manually generate mesh over some regions. To generate clean flow of mesh we have to smooth the mesh. To eliminate tria we have combine opposite direction tria by dragging then over one another. Some of the element fails for quality in such condition we can used element optimization tool or element cleanup tool.
There are some ground rules to be taken into consideration:
1) Optimizing use of tria element.
2) Eliminating rotational Quads.
3) Placing the tria elementin the middle of geometry i.e avoid use of tria element on the edges.
4) Do not place tria element in fillet region.
3) To check the Quality Parameter of elements.
- i) Tools – check Elements – parameters
Manually elimination the poor quality elements.
ii) To check whether the element is associated with surface
Mesh – Element - Comparison of element with surface.
The elements highlight in blue, pink are acceptable element. We have to eliminate red coloured elements.
To eliminate Red eliminated go to Tools – Project – Surfaces – from element to surface.
- ii) To check the normal direction of elements.
The direction of normal should be in similar direction then only the element will react similar to loading conditions.
Tools – Normal –Displayed
Make sure the elements are displaying similar colour. If not manually reversing the direction of normal.
iii) To check the dependency of element and penetration.
The element should not depend on more than 1 element if so the element will fail while solving the loading condition. Penetration toll is to check whether elements are not overlapping or intersecting
iv) To Associate thickness to model
Material – Steel – Isotropic – MAT1 – Create
Properties – Material - Steel
Components – properties - Properties
4) In some cases we can reflect the elements when the component is symmetry.
In case of outer panel we can generate mesh on half of side and then reflect the elements. This will reduce our time taken for meshing.
Also we can reflect mesh from hinged body 1 to hinged body 2 using reflect panel.
This process is applicable to all the components.
Conclusion: We got to know some tools which will improve the accuracy, quality and reduce the meshing time. We got to know how to Automesh , Quality Index, Removing of rotational Quad, eliminating tria, smoothing the element flow, changing the quality parameter, Auto cleanup and its parameter, importance of washer, projection of nodes.
Result: From this Challenge we got to know the tools to generate mesh and to cleanup the quality of elements. We also got to some technics to generate mesh effectively.
Final component:
1) Inner Panel
2) outer panel
3) hinge reinforcement extract body 1 and body 2
4) Latch reinforcement extract body 1