Fender Design - Wheel Arch Challenge

WHEEL ARCH CALCULATIONS

What is Wheel Arch?

• Wheel Arch is the semi-circular part of the fender positioned above the wheel of the vehicle.
• The design of the Wheel arch of a fender should be such that is must shield wheels and protect both passenger’s compartment and pedestrians from the projection of water, mud and stones.
• For the vehicle to use it has different permits in different countries, the wheel arch offenders must be compliant with the standards and regulations set by the respective countries.

Types of Wheel Arch regulations:

1. Japanese Regulations

• Measure clearance L of the tire, hub, cap and fender in three different positions within area K and produce a clearance check chart to validate.
• Clearance must be greater than 5mm in all three positions.
• The value of A must be greater than 5mm at 30 degrees forward and 50-degree rearward from the central vertical axis to the axis wheel.

2. European Regulations

• Measure CL L at sections SA-SA SB-SB SC-SC SD-SD SE-SE and produce Cl check chart to validate.
• At all the five sections CL L value should be greater than 10mm to satisfy the ‘European Regulations’.
• The value of A shall be more than 5mm at line 30 degrees forward and 50 degrees rearward from the central vertical axis to the axis of the wheel.

3. US Regulations

• Make a clearance check details on all the positions from -100 deg. To 100 deg. And make the clearance check table.
• All the values should be greater than 5mm to satisfy the regulations.
• The value of A shall be greater than 5mm at a line 30 deg. Forward and 50 deg. rearward from the central vertical axis to the axis of the wheel.

Obtaining Result:

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’.

1. Measuring ‘L’ for the given wheel and fender at SA:

The value of ‘L’ at SA = 9.9490mm

2. Measuring ‘L’ for the given wheel and fender at SB:

The value of ‘L’ at SB = 10.000mm

3. Measuring ‘L’ for the given wheel and fender at SC:

The value of ‘L’ at SC = 0.1139mm

4. Measuring ‘L’ for the given wheel and fender at SD:

The value of ‘L’ at SD = -2.9520mm

5. Measuring ‘L’ for the given wheel and fender at SE:

The value of ‘L’ at SE = -6.1570mm

Clearance “a” for Wheel Guard Requirement:

1. Finding the value of “a” at line 30 deg. forward from the centre vertical axis of the wheel.

The value of “a” at line 30 deg. forward from the centre vertical axis of the wheel =

2. Finding the value of “a” at line 50 deg. rearward from the centre vertical axis of the wheel.

The value of “a” at line 50 deg. rearward from the centre vertical axis of the wheel =

Clearance TABLE:

From table 1, the given fender doesn’t pass the European standards for the wheel arch area at sections SA, SB, SC, SD, and SE.

From table 2, the given fender passes the European standards for the wheel arch area at sections SA, SB, SC, SD, and SE.

Suggestions:

The styling team is required to modify the styling surface of the fender such that the clearance “L” at sections SA, SC, SD, SE is equal to or greater than 10mm by increasing the curvature at those sections towards the outside.