Fender Design - Wheel Arch Challenge

Fender Design - Wheel Arch Challenge

Scope:

We have going to evaluate the Wheel Arch gap at required points for the given Wheel Arch Part file bodys with respect to European standard then confirming wthether the provided fender getting pass or fail.

Fender - Wheel Arch

Fender is the side closing component for the engine compartment. It’s major role is to avoid chipping sand, small stones and mud particles inside the engine compartment when the wheels rotate. Fender also plays a major role to prevent injuries for the pedestrians. Basically we have two types of fender half bumper type and the full bumper type. The difference between two types are its size. The raw material usage plays a major role and so half bumper is economical.Drip area and wheel arch are one of the two important things to be considered while designing fender.

Wheel Arch:

There are standards all over the world for wheel arch of a car. Country to country they will fix a certain regulation considering the infrastructure available in their country. Basically when the wheel is seen from the front side and if it was outside the car the chipping will be more and that causes damage to the engine compartment and the pedestrians.

Fender Wheel Arch Regulations:

Japan Regulations:

1. The clearance ‘L’ for tire, hub, cap and fender is to be measured within area K and create clearance check chart to validate.
2. The value of L should be greater than 5mm at all positions.
3. Wheel guard requirement: The value of ‘a’ should be more than 5mm at line 30° forward and 50° rearwards from the central vertical axis of the wheel.

US Regulations:

1. Clearance ‘L’ is to be checked at all positions from -100° to 100° and create clearance check chart to validate.
2. The value of L should be greater than 5mm to satisfy the regulations.
3. Wheel guard requirement: The value of ‘a’ should be more than 5mm at line 30° forward and 50° rearwards from the central vertical axis of the wheel.

   European Regulations:

   1. The Clearance ‘L’ should be measured at sections SA-SA, SB-SB, SC-SC, SD-SD and SE-SE and create clearance check chart to validate.
   2. At all the five sections the value of L should be greater than 10mm to satisfy the European Regulations.
   3. Wheel guard requirement: The value of ‘a’ should be more than 5mm at line 30° forward and 50° rearwards from the central vertical axis of the wheel.

   

Calculation of wheel arch area according to European Regulations Using NX-CAD:

For calculation of clearance between Wheel Arch and Wheel we have to create a sketch on the outer most face of the wheel. The procedure of which is given below.

1. A Datum Plane is created at the outermost face of the wheel .
2. The sketch is created on the new Datum Plane.
3. A Horizontal line is drawn across the centre of the wheel.
4. A perpendicular line SA is dropped at the centre of the wheel.
5. Two lines SB and SC are created at 30° forward of SA and 50° rearward of SA respectively.
6. A point is created 150mm vertically above the centre line.
7. A line SE is drawn from the wheel centre and passes from the point created.
8. Another line SD is drawn from the centre of the wheel and in the middle of lines SC and SE. Sketch:

   Obtaining the clearance L at the designated 5 points

   The clearance distance 'L' is calculated at points SA-SA', SB-SB', SC-SC', SD-SD' and SE-SE', which should be greater than or equal to 10mm.

   i.) Clearance 'L' at SA-SA'

   ii.) Clearance 'L' at SB-SB' iii.) Clearance 'L' at SC-SC' iv.) Clearance 'L' at SD-SD' v.) Clearance 'L' at SE-SE'

   SECTION	L - VALUE	RESULTS
   SA - SA'	9.949 MM	FAIL
   SB - SB'	10.0000 MM	PASS
   SC - SC'	-0.113 MM	FAIL
   SD - SD'	-2.887 MM	FAIL
   SE - SE'	-5.997 MM	FAIL

   The following spec Vs Actual found with evaluating by inputs of european standards of regulations,

   • Spec "L" required SA is 10mmbut in actual SA is 9.949mm and the resultabout SA is fail.
   • Spec "L" required SB is 10mmbut in actual SB is 10.0000mm and the resultabout SB is Pass.
   • Spec "L" required SC is 10mmbut in actual SA is -0.113mm and the resultabout SC is fail.
   • Spec "L" required SD is 10mmbut in actual SA is -2.887mm and the resultabout SD is fail.
   • Spec "L" required SE is 10mmbut in actual SA is -5.997mm and the result about SEis fail.

   From the above observations the positions SA SC SD SE are less than 10mm which is necessary to pass the European standards. Hence, the front fender wheel arch does not pass the European standard.

   I would share my feedback/report to styling team and asking to that, you required to modify the styling surface of the fender such that the clearance "L" at sections SA, SC, SD and SE is equal to are greater than 10 mm by increasing the curvature at those sections towards outside.

   Calculation of wheel arch area according to European Regulations Using CATIA: