Project 1 - 2D meshing on the instrumental Panel

AIM: Pre-processing of the car instrument panel using ANSA

OBJECTIVES:-

• Introduction to shell meshing or 2 D meshing
• Topological errors and geometry errors clean-up.
• Extracting mid surface with a different method.
• Meshing the geometry within quality parameters. Rectifying quality errors ie solving off elements.
• Improving mesh flow pattern.

INSTRUMENT PANEL:

The instrument panel is a control panel for the driver of the vehicle which is situated ahead of the driver's seat The instrument panel includes a speedometer, fuel gauge. airbags, steering columns, media control panel, glove box bean, air ducts, side indicators, seatbelt warning. GPS navigator, mobile holder, etc. As the largest inner trim part directly shown to the passenger, the instrument panel has not only beauty and function required but also NVH and safety requests. The vibration and the noise on the dashboard can be directly felt by the passenger.

Thus, the FEA analysis of the instrument panel plays a very important role in the whole vehicle's NVH character. The substrate may be formed fiom a rigid material, such as metal or rigid plastic The instrument panel doesn't necessarily need to have heavyweight material to keep the part intact, rather it can be done using the part that is lighter, save costs. But we need to make sure that the material is rigid and design good enough so the material does not fail in NVH

Procedure:Opening the File:

• The file is downloaded initially. To open the file, follow the steps. Open ANSA >> Give Command Arguments >» OK » Click Ctrl •O (for opening the file) >> Select the File» Click Ok
• On the Whole to describe the Opening of a file, click on the ANSA app, and wait for the launcher dialog box to appear.
• Once it appears, the dialog box contains the information called Additional ANSA command arguments are seen there will be an input box just below it.
• The argument has to be changed to "-performance_mode 3" (This means the performance of the app and it has Slower drawing and yet better quality.) then click ok to continue.
• The ANSA is now opened and then you can either open the file by using file option and open or Ctrl

. Checking the Geometry:

• This process is just used to check the topology of the model. In order to check the Topology follow the process as Tools» Checks » Geometry» Execute.
• Once executed, it might show a green bar stating there are no errors in the geometry or it may show the dialog box showing the errors present in it.
• These errors can be fixed either by going on with them individually or once Right- clicked on the mouse an additional list pops- up.
• Fix option will be present in that pop-up when it is clicked the errors which can be fixed are executed and it might contain only a few errors which should be fixed manually and if no errors are present then it will show the green bar stating executed
• The process is called geometric clean- up. It can be done either completely or part- wise of the parent geometry

check the geometry

Measurment the thickness of PI

Creating the Mid-surface:

The Mid-surface is created by using different methods such as Automatic Mid-Surfacing like Skin, Casting, and manual Mid-surfacing methods like Offset.

Generating a Mesh:

• The mesh can be created in two ways Automatic Mesh or Manual Mesh. Automatic Mesh is created as the batch mesh and Manual mesh is created as spot, best, etc.
• The Batch Mesh can be selected from Tools manager or by clicking Ctrl B.
• Tools Manager >» Batch Mesh >» New >» Meshing Scenario >> Select the Mid surface by double clicking >» Select PID >» Click Ok >> Give the Meshing Parameters and Quality Criteria >» Click Run

Mid surface generation for dog houses

For generating the mid surface of dog houses, Dog houses in this model captured as "Cross pattern" in Mid surface since dog houses are solid and are not having any thickness. I used the Curves -> Middle option and then I created a surface using curves and extended it to the surface.

QUALITY CRITERIA SETUP:

We must assign quality parameters such that meshing elements will get measured from their ideal shape. The parameters like warping skewness, aspect ratio, etc. have to be given in the quality criteria setup meshing parameters also have to give before meshing such that surface will get mesh under given length.

DEFEATURING:

Defeaturing means removing unnecessary construction lines and curves in the CAD model because of manufacturing constraints we have to remove them or arrange them properly for a better mesh flow without failing quality criteria Very small entities can be a problem if you have a very small face with sharp angles, meshing might get fail. Therefore check the CAD model for very small entities and remove therm before creating a mesh for it.

MESHING:

Meshing is an integral part of the engineering simulation process where complex geometries are divided into sirmple elements that can be used as discrete local approximations of the larger domain, It is a network that is formed of cells and points Now we can finally mesh the component after defeaturing the complex areas there must be better mesh flow in the component, Before starting meshing we have to set the perimeter elemental value as 4mm so that perimeter points will be arranged within the limit in the surface edges

Most of the quality issues will be seen in the areas of nbs and features. We will Reconstruct the Macroregion or rearrange the construction line in such areas. The other areas where there will be quality issues will be the area where triple cons intersect, or triple cons are

We need to make sure that the PID of all parts is set before we begin meshing Property id can create by selecting the SET PID option under the face module button.

Assing the thickness of PI

Final

CONCLUSION:

The panel had been captured quite a well-using shell mesh. The total element 44104 out of which 2022 are Tria element and 42082 are Quads which makes 4.58% which is a decent percentage of Tria elerment.. Most of the areas of fillets are captured using dach options and defeaturing is done in areas where construction lines are too close. The mesh flow is smooth nearer to the target length of 4 mm and within the quality parameter.

LEARNING OUTCOMES:

• Geometry cleanup and performing topology Generating Midsurface
• Assigning quality criteria and mesh parameters
• Able to understand and implement good practices of meshing any complex geometries.

DRIVE

https://drive.google.com/file/d/1cXByjxIwgdxoHDcP4DcoQ813wILJdBU2/view?usp=drivesdk