Week 6-Meshing of Hood Challenge

AIM :-

To mesh the hood on basis of given criteria.

GIVEN MODEL :-

QUALITY CRITERIA :-

Target Element Length = 5 Units

S.N	Quality Criteria	Value
1	Aspect Ratio	5
2	Skewness	45
3	Warping	15
4	Taper	0.5
5	Min. Length	2 Units
6	Max. Length	8 Units
7	Min angle Quad	45
8	Max angle Quad	135
9	Min angle Tria	20
10	Max angle Tria	120
10	Tria %	10

STEPS :-

1. Importing geometry and cleanup.
2. Extracting Mid-surface and assigning properties.
3. Meshing the surface with in the given quality criteria.

THEORY :-

The hood (North American English) or bonnet (Commonwealth English) is that the hinged cover over the engine of cars. Hoods can receptive allow access to the engine compartment, or trunk (boot in Commonwealth English) on rear-engine and a few mid-engine vehicles) for maintenance and repair.

In recent years, the work has been done on the bumper and hood design of the vehicle forepart to scale back the injuries to the pedestrians within the event of a pedestrian vehicle collision. The front portion of the vehicle gets damaged including bonnet when met with an accident. So there's have to change the present design of bonnet or by changing the fabric. The bonnet is that the hinged cover over the engine of automobiles that permits access to the engine compartment for maintenance and repair. Bonnet usually don't directly open onto the passenger cell which greatly reduces the importance (weighting) of certain of the functional requirements normally related to closures like air tightness, passenger safety, low cycle fatigue strength etc. the target of those measures is to cut back the amount of road accident fatalities and therefore the severity of injuries sustained by pedestrians involved during a collision with a vehicle in urban traffic. Impact frequency and seriousness of injury has been studied for several years, leading to rating systems and improved design. The bonnet system is an access panel to the engine compartment to enable maintenance of geartrain, drive belts, battery, fluid levels and lamp units. it's fundamentally a reinforced skin panel with many Safety and quality requirements.

Engine Hood:

The hood which is additionally called ENCON, is an access panel to engine compartment of an Automobile, it's an assembly product of Outer and Inner panels to satisfy various safety and style requirements.

The followings are the planning considerations involved within the design of Engine Hood.

• Pedestrian Safety
• Vehicle quality
• Occupant Safety
• Styling
• Manufacturability

Types of Hoods:

• Invalid Hood or inbuilt
• Wrap Around Hood
• Hood With Fenders
• Hood with Border Diagonal Frames
• Hood with Brace Frames

PROCEDURE :-

Step 1: Importing geometry and cleanup:

• To import the geometry, go to file >> Import >> select the file >> Import.
• After importing the geometry, the geometry is checked for any missing surfaces or triple cons. If there are no errors present in the geometry then the geometry is ready for the mid-surface extraction.

Step 2: Extracting mid-surface and assigning properties:

• Mid-surface can be extracted by any of the methods below.
  1. Offset + plane + sweep.
  2. Offset + plane.
  3. Skin Offset.
• To extract the mid-surface, go to geom >> mid-surface >> select any extraction option >> select the surface >> extract. In this challenge offset + plane + sweep is used.
• After extracting the mid-surface, it is checked for any geometrical errors like needle faces, missing surfaces and triple cons. If any of the errors present then it should be rectified immediately.
• Now the properties like thickness, material etc. need to be assigned to the mid-surface. To assign the properties, select model in database and right click and choose create and then property.
• Now all the properties are entered in the property tab and the properties are assigned to the respective mid-surfaces.
• To assign the properties to mid-surface, right click on the mid-surface and then select assign and select the respective properties which needs to be assigned.

     

Step 3: Generating mesh within the given quality criteria:

• Before generating mesh, the geometry is cut into smaller rectangles for good mesh flow.
• To generate mesh, go to 2D >> automesh >> select the surface >> mesh. To edit the mesh for proper flow, the elements are selected and meshed again.
• If any elements are failing for quality then cleanup tools option which is present in quality index can be used.

  

 

Conclusion :- 

The mesh is done on the basis of given quality criteria.