Project 1 - 2D meshing on the instrumental Panel

AIM: To perform geometrical cleanup and extracting the midsurface and to generate 2D mesh for the given component. 

OBJECTIVE:

For the given component, check for the geometrical errors and mesh with the given element Quality criteria. After meshing the component the thickness has to be assigned.

Write a detailed report on your meshing process and also mention which method you used to extract the mid-surface along with the reason.

 

S.No	Quality Criteria	Value
1	Target/Average length	4
2	Minimum Length	2
3	Maximum Length	6
4	Aspect	3
5	Warpage	15
6	Skewness	45
7	Jacobian	0.7
8	Minimum Quad Angle	45
9	Maximum Quad Angle	135
10	Minimum  Tria Angle	30
11	Maximum Tria Angle	120
10	Tria Percentage	15

 

 

Introduction:

IP console:-

The accronym of IP is instrument panel. It is also known as a Dashboard (also called dash), is a control panel set within the center console of a vehicle. Usually located directly ahead of the driver, it displays the  instrumentation and controls for the vehicle's operation. IP console appears as shown in the below figure.

                            

Usually, It is made up of plastic(With the varying thicknesses) in the modern cars. And the position of IP console in the cars will be as shown in below figure. 

 

  

Polyvinyl Chloride, more commonly known as PVC, is a flame retardant plastic that can be formed into either flexible or rigid components. Which is often used for manufacturing dashboards and automotive body parts.

Necessity of meshing IP console:

As the IP console undergoes various shock waves during the accident, So, various analysis is needed to be performed. For analysing, the continous domain is splitted (or) discretized into so many parts in the form of elements which are joined by nodes. Which is commonly known as "Mesh".

After generating the mesh, variuos types of analysis such as durablity analysis, NVH analysis etc can be performed. Inorder to get the various types of stresses in the form of outputs. So that the further modifications like changing the materials, properties can be done(If necessary).  

 

Procedure:

Step 1: Pre-requisites:-

Initially, The given component is imported in to the software tool. After importing, the given component in graphical display appears as shown in fig 4.1.

                       

                                                                      fig 4.1

After importing, the topo clean up is to be done. Inorder to have connection among the surfaces. So, "Clean geometry" option from Hot points in topo module is used. As shown in fig 4.2.

                                                      

                                                                      fig 4.2

After performing topology clean up, the component with the connected edges(represented by yellow coloured lines) appears as shown in fig 4.3.

                 

                                                                      fig 4.3

Then the orientation of all faces is fixed, Inorder to have  by using "Orient" option from faces in topo module. As shown in fig 4.4. 

                                                 

                                                                   fig 4.4

After performing the topo clean up, all faces appears with same colour representation(either grey or yellow). As shown in fig 4.5. 

                   

                                                                    fig 4.5

Then the given geometry is checked by using "Geometry---> Checks". As shown in fig 4.6.

               

                                                                      fig 4.6

After choosing the "Checks" option, a dialog box appears as shown in fig 4.7. In which the aspects required for the geometry check are enabled. By clicking on "Execute" the geometry will be verified.

               

                                                                   fig 4.7

After verifying, the errors with respect to the geometry will be shown. As seen in fig 4.8.

                

                                                                      fig 4.8

Step 2: Geometry clean up:

Some of the errors can be fixed automatically. By using "Fix" option. Some errors should be fixed manually. By enabling the faces which are failing. By enabling those faces, it appears as shown in fig 4.9.

                  

                                                                        fig 4.9

The neighbouring faces are enabled. As shown in fig 4.10.

                  

                                                                   fig 4.10

The faces which are failing, are deleted. And the unwanted hot points are deleted. After deleting those faces, it appears as shown in fig 4.11.

                  

                                                                     fig 4.11

New faces are created in those regions. By using "New---> seleting the Coons" option. As shown in fig 4.12.

                  

                                                                fig 4.12

After creating a new face, it appears as shown in fig 4.13.

                  

                                                                   fig 4.13

Similarly, all geometrical errors are to be cleared before meshing. After clearing all geometrical errors, 100% error free geometry indication appears as shown in fig 4.14.

                  

                                                                 fig 4.14

Step 3: Mid-surface extraction:

Then distances are measured in various regions, to get a clarity on the thicknesses of various parts. This is done by using "Measure" option from utilities panel. After measuring, the given component with measurements appears as shown in fig 4.15. 

                        

                                                                fig 4.15

After measuring, the conclusion with the thickness of base plate is approximately 0.6 mm. So, the mid-surface is extracted for the base plate using "Offset" option from faces in topo module. As shown in fig 4.16.

                                                

                                                                     fig 4.16

Inoder to select only the base plate, the "Feature angle" option is enabled. As shown in fig 4.17. 

                                                    

                                                                      fig 4.17

After choosing the feature angle option & by selecting one face, all faces associated with the value of feature angle (i.e., faces of base plate) will be slected. Then by middle clicking on mouse, a dialog box appears as shown in fig 4.18. In which the offset value is entered(Offset value = Half of the thickness of the component selected).

                   

                                                                      fig 4.18

By middle clicking on mouse, a mid-surface will be extracted. The extracted mid-surface for the base plate appears as shown in fig 4.19. 

                    

                                                                  fig 4.19

But at some regions as shown in fig 4.20, the faces need to be filled. 

                

                                                                     fig 4.20

Then by using "New" option from faces in topo module, the new faces are created(Option used in new for selecting the cons is "Coons"). As shown in fig 4.21

                

                                                                       fig 4.21

Then the mid-surface is extracted for the ribs. For extracting the mid-surface easily for ribs, the "Middle" option from curves in topo module is used. As shown in fig 4.22.

                                                         

                                                                          fig 4.22

By selecting the pair of lines(or) edges, a middle curve will be generated. Which is represented by purple coloured line, as shown in fig 4.23.

                     

                                                                         fig 4.23

Similarly for the other ribs also, the curves are extracted. After generating the middle curves & by enabling only them, it appears as shown in fig 4.24

                         

                                                                fig 4.24

Then the new faces are created in between these curves, As shown in fig 4.25. By using "New" option from faces in topo module.

                    

                                                                    fig 4.25

Then the created curves are projected by using "Project" from cons in topo module. As shown in fig 4.26.

                    

                                                                    fig 4.26

After projecting, a con is formed on the selected face. As shown in fig 4.27. Which splits the face and led to the formation of a new face between the curve & projected con(Which replicate the parent geometry in mid-surface).

                   

                                                             fig 4.27

After creating a new face, it appears as shown in fig 4.28.

                   

                                                               fig 4.28     

In some regions such as shown in fig 4.29, the two surfaces which are to be connected(As in parent geometry). But they will not be associated with each other. So, To connect those two surfaces "Extend" option from faces in topo module is used. Initially, the face to be extended is selected(in the form of green coloured line) and then target face is selected. 

                   

                                                               fig 4.29

After extending, the faces with the connection appears as shown in fig 4.30.

                   

                                                               fig 4.30

Then the mid-surface is extracted for the remaining ribs. The mid-surface is extracted by creating a curve at the middle, As shown in fig 4.31. And this curve is projected & a new face is created between them. 

                                            

                                                                fig 4.31

To extract the mid-surface for ribs as shown in fig 4.32, Middle curve option will not be helpful(Because At the time of projection of curve on to a face, it will not project well). So, offset option is used. So, For that the thickness is measured. 

                    

                                                                  fig 4.32

The faces to do offset is selected. As shown in fig 4.33. By mentioning the offset value, the mid-surface is extracted for the rib.

                    

                                                                 fig 4.33

After extracting the mid-surface to that rib, it appears as shown in fig 4.34. 

                               

                                                                   fig 4.34

Then to have connection between two faces, the extracted mid-surface for the rib is extended. After extending, it appears as shown in fig 4.35.

                               

                                                             fig 4.35

As seen in fig 4.35, the two surfaces are overlapped with each other. So, The "Intersect" option from faces in topo module is used. Inorder to intersect(Split) the faces. As shown in fig 4.36.

                    

                                                             fig 4.36

After intersecting the faces, the splitted faces will appear as shown in fig 4.37. And the unwanted faces below the target face are deleted.

                              

                                                            fig 4.37

Then the mid-surface is extracted for the cylinder shaped components. The mid-surface is extracted by creating the two curves manually & perpendicular to each other. As shown in fig 4.38.

                              

                                                            fig 4.38

Then these curves are projected on to the base face. And a face is created between those cons. After creating the new faces, it appears as shown in fig 4.39. 

                   

                                                                 fig 4.39

Similarly, the mid-surface is extracted for all cylindrical components.

Finally after extracting the mid-surface, it appears as shown in fig 4.40.

                     

                                                                fig 4.40

Step 4: Mesh generation:

Next step is to generate the 2D mesh. Before generating the mesh, there are some pre-requisites. They are:-

• Setting up the mesh parameters. As shown in fig 4.41.
• Setting up the quality criteria. As shown in fig 4.42

                  

                                                                 fig 4.41

After choosing the quality parameters, by clicking on "Apply" & "OK" the quality criteria will be assigned.

                 

                                                               fig 4.42

Then length between the two nodes are assigned by using "Length" option from perimeters in mesh module. And by entering the target element length in the dialog box as shown in fig 4.43, the length will be assigned.

                  

                                                               fig 4.43

Then by enabling the "Hidden" panel, the whole component appears black in colour by show-casing the entered quality criteria. As shown in fig 4.44.

                            

                                                                fig 4.44

Then the mesh is generated by using "Spot mesh" option from mesh generation in mesh module & by selecting the faces on which the mesh is to be generated. As shown in fig 4.45.

                   

                                                                fig 4.45

After generating the mesh, it appears as shown in fig 4.46. With some elements failing for the quality criteria assigned.

                                                

                                                                fig 4.46

The elements failing can be elemeninated by using "smooth" option from shell mesh in mesh module. As shown in fig 4.47.

                                               

                                                                  fig 4.47

After performing smooth, the generated mesh by eleminating the failed elements appears as shown in fig 4.48.

                                             

                                                                     fig 4.48

Similarly, the mesh is generated face by face. After meshing the entire component, it appears as shown in fig 4.49. 

                     

                                                                        fig 4.49

Then the elements failing for the assigned quality criteria is concentrated. And the failed elements are reduced to some extent from 699 to 385 elements. As shown in fig 4.50

                                                                                                      fig 4.50

Step 5: Assigning thickness:

Next step is to assign the thickness. The thickness is assigned by using "Draw shell as solid" from presentation parameters in quality criteria panel. As shown in fig 4.51. By clicking on Apply, the thickness will be assigned.

Note: Before assigning the thickness, the various PID's should be created by various thicknesses.

                    

                                                                 fig 4.51

After assigning the thickness, the generated mesh with the assigned thickness appears as shown in fig 4.52.

                     

                                                                 fig 4.52

Finally after assigning the thickness, the given component with the generated mesh appears as shown in fig 4.53.

                           

                                                                fig 4.53

 

 

 

CONCLUSION: 

In this challenge I have performed geometry cleanup for the given IP console and then extracted the midsurface for the given component and generated 2D mesh on the midsurface and the appropriate thicknesses has been assigned for the given component.

 

 

Drive link for the worked model:- 

 

 https://drive.google.com/file/d/1VEl2Fvxou3vQXYLwobap41UNCMRLyVxv/view?usp=sharing