Fender Design - Wheel Arch Challenge

Aim: To Calculate the Wheel Arc area and prove whether the car will pass the standards or Not. Using the European Standards.

Wheel Arch:

• It is a semicircular profile above wheels designed for enclosing tires within the fender. The wheel arch is designed considering all possible motions the tire undergoes while the vehicle is in motion
• The wheel arch also ensures stopping any debris that could fly outside the wheel well and hit pedestrians.

European Standards for Wheel Arch of an Automotive Fender Design:

Design Data Received

Software Used: Catia V5

Procedure

1. Take a Point on the center of the wheel
2. Create a plane on the point
3. Project the fender Curve and the wheel outer edge onto the plane using the project 3D element Command in the sketch workbench
4. Now Create horizontal and vertical Axis (SA) lines using the point we created for the plane
5. Now Create Two lines using the same point one at 50 deg anti-clockwise (SC) and another one at 30 deg clockwise (SB) from the vertical axis (As shown in fig)
6. make them coincident with the projected fender Curve
7. Next, take a point on the fender curve at a height of 150mm from the horizontal axis line
8. Draw one more line (SE) which passes through that point making a coincidence relation
9. Sketch a line (SD) in between the lines SC & SE

The sketch is drawn on the wheel face as per the European standards provided and projected on the wheel arch at sections SA, SB, SC, SD, and SE to measure "L", "a", and wheel arch area.

Obtaining the value of clearance "L"

a) Measuring "L' for the given wheel and fender at SB:

The value of "L" at SB = 10 mm

b) Measuring "L' for the given wheel and fender at SA:

The value of "L" at SA = 9.94 mm

c) Measuring "L' for the given wheel and fender at SC:

The value of "L" at SC = 0.114 mm

Table A: Clearance "L" obtained at sections SA, SB, & SC,

From the outer edge of the Fender	Required Clearance Length(mm)	Acquired Clearance Length(mm)	Results
SA	>5	10	PASS
SB	>5	9.94	PASS
SC	>5	0.114	FAIL

From table A, the given fender doesn't pass the European standards for wheel arch area at section SC as it didn't reach the required standard clearance value which is greater than 5 mm

Obtaining the value of "a"

Measuring of the value of "a" at all the five Sections SA-SA, SB-SB, SC-SC, SD-SD, & SE-SE

Table B: Value of "a" obtained at all the 5 Sections

Sections	Required Length (mm)	Acquired Length (mm)	Results
SA-SA	>10	25.992	PASS
SB-SB	>10	43.641	PASS
SC-SC	>10	38.361	PASS
SD-SD	>10	42.662	PASS
SE-SE	>10	47.625	PASS

Conclusion: As from the above analysis the given fender design doesn't pass the required clearance "L" need at the point "SC" is 0.114 which is less than the minimum required clearance ie;(>5) according to European Standards. So, the design is sent back to the Class a team with feedback about an increase of the clearance at the "SC"