Fender Design - Wheel Arch Challenge

Wheel Arch Gap

Objective:

Calculate the Wheel Arch gap at required points and check whether the car passes the European standard.

Introduction:

The Wheel Arch is a curved/semicircular part positioned above the wheel of a vehicle. Space in the body of a vehicle over a wheel, shaped like an arch is called a Wheel Arch Gap. The Wheel Arch is designed in such a way that it protects both the pedestrian and car cabin from mud, water rocks, and other road sprays. Different countries have different wheel arch regulations, and the wheel arch design has to comply with the country specified standards and regulations. For avoiding design alterations of the fender of the same vehicle to meet the different regulations in different countries, the maximum value of the Wheel Arch Gap parameters of the countries is taken into consideration for design purposes.

Fender Wheel Arch Regulations:

1. Japan Regulations:

The clearance 'L' for tire, hub, cap, and fender in three different positions is to be measured within area K and produce a clearance check chart to validate.

The clearance 'L' must be greater than 5 mm in all three positions (B, A, and C).

To calculate Wheel Arch Gap, three lines are drawn from the wheel surface, from the central vertical axis 'A', at 30° forward to the central vertical axis 'B', and at 50° backward to the central vertical axis 'C'.

2. European Regulations:

Measure clearance 'L' at SA-SA, SB-SB, SC-SC, SD-SD, SE-SE, and a clearance check chart to validate.

In all five sections, the clearance value 'L' should be greater than 10 mm to satisfy European regulations(SB, SA, SC, SD, and SE).

To calculate Wheel Arch Gap, three lines are drawn from the wheel surface, from the central vertical axis 'SA', at 30° forward to the central vertical axis 'SB', and at 50° backward to the central vertical axis 'SC'. At a distance of 150 mm from the central horizontal axis, a line is drawn 'SE', and a line 'SD' is drawn bisecting the two 'SC' and 'SE'.

3. US Regulations:

Make clearance and check on all positions from -100deg to 100deg and make a clearance table.

All values should be greater than 5 mm to satisfy the regulations.

Calculations of Wheel Arch Gap - European Regulations:

To calculate the clearance between the wheel arch and the wheel, create a sketch on the outermost face of the wheel.

Make a central horizontal axis line, a central vertical axis line 'SA', a line SB at 30° forward to the central vertical axis, and a line SC at 50° backward to the central vertical axis 'SC'. At a distance of 150 mm from the central horizontal axis line, draw a line 'SE', and a line 'SD' by bisecting the two 'SC' and 'SE'.

Using the Simple Distance option in the analysis tab, the distance was measured to check and validate as per the European standard.

1. Clearance 'L' at SB:

'L' SB = 10.00 mm

2. Clearance 'L' at SA:

'L' SA = 9.9489 mm

3. Clearance 'L' at SC:

'L' SC = -0.112637 mm

4. Clearance 'L' at SD:

'L' SD = -2.8468 mm

5. Clearance 'L' at SE:

'L' SE = -5.9018 mm

Results:

Section	Required Clearance 'L' (mm)	Actual Clearance 'L' (mm)	Comment
SB	10.00 mm	10.00 mm	PASS
SA	10.00 mm	9.9489 mm	FAIL
SC	10.00 mm	-0.1126 mm	FAIL
SD	10.00 mm	-2.8468 mm	FAIL
SE	10.00 mm	-5.9018 mm	FAIL

From the above results, we can conclude that the design fails to comply with the European Regulations.

Conclusion:

The Wheel Arch Gap at required points has been checked following the regulations of the European standard.