Fender Design - Wheel Arch Challenge

REPORT

FENDER

Fender is the american english term for the part of an automobile or other vehicle body that frames a wheel well (the fender underside). Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire. Fenders are typically rigid and can be damaged by contact with the road surface.

Sticky materials, such as mud, may adhere to the smooth outer tire surface, while smooth loose objects, such as stones, can become temporarily embedded in the tread grooves as the tire rolls over the ground. These materials can be ejected from the surface of the tire at high velocity as the tire imparts kinetic energy to the attached objects. For a vehicle moving forward, the top of the tire is rotating upward and forward, and can throw objects into the air at other vehicles or pedestrians in front of the vehicle

The fender's openings for the wheel wells tend to be much larger than the diameter of the tire, because they do not move with the tire suspension and consequently must be large enough to allow the full range of tire motion on the suspension without touching the interior of the wheel well.

FENDER 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 the fender should be such that it must shield wheels and protect both passengers compartment and pedestrians from the projection of water, mud and stones.The wheel arch area of the fender is usually designed as a cover or shield over the tyre along its perimeter to stop any debris or stones,dirt,sand,snow,etc, from getting thrown into the vehicle or the BIW area as well as outside the vehicle and onto other vehicles or pedestrians on the road.For the vehicle to has its permit in different countries, the wheel arch of fenders must be compliant with the standards and regulations set by respective countries.

JAPAN REGULATION

• The clearance ‘L’ for tire, hub, cap and fender is to be measured
• The value of L should be greater than 5mm at all positions
• 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 REGULATION

• Measure CL L at sections SA-SA, SB-SB, SC-SC, SD-SD, SE-SE, and produce CL check chart to validate.
• At all five sections, the CL L value should be greater than 10mm to satisfy the European regulations.
• Wheel guard requirement: The value of 'a' shall be more than 5mm at a line 30° forward and 50° rearward from the central vertical axis of the wheel.

US REGUALATION

1. The values calculated for every 10 degrees and All values should be greater than 5 mm.
2. Wheel guard requirement: The value of ‘L’ shall be more than 5 mm 30˚ forward and 50˚ rearward from the central vertical axis of wheel.

OBJECTIVE

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

PROCEDURE

• Create a datum plane on outer face of wheel
• Sketch on the datum plane as per requirement for European regulation .
• A horizontal axis is drawn from the centre of wheel ‘S’.
• A vertical line drawn from the centre of the wheel ‘A’.
• Line is drawn 30° forward and 50° rearwards from the central vertical axis of the wheel B and C respectively
• A 150 mm perpendicular line is drawn from horizontal and draw the line E
• Draw the line D through midpoint created on arc between C and E
• Project the lower curve of fender on this datum plane and mark the intersection point between lines and projected curve.
• Finish the sketch and project the five intersection points on fender face.
• Then measure the distance between the points.

1)measuring the distance between SA and the corresponding point on wheel arch face

clearence =9.9490

2)measuring the distance between SB and the corresponding point on wheel arch face

clearence =10mm

3)measuring the distance between SC and the corresponding point on wheel arch face

clearence =-0.1139 (the tyre is outward from the wheel arch face)

4)measuring the distance between SD and the corresponding point on wheel arch face

clearence =-2.8621

3)measuring the distance between SE and the corresponding point on wheel arch face

clearence =-5.9409

CONCLUSION

At all five sections the wheel arch gap as per the european regulation , the value should be greater than 10mm.

section	clearence 'mm'	pass/fail
SA	9.9490	fail
SB	10	pass
SC	-0.1139	fail
SD	-2.8621	fail
SE	-5.9409	fail

the Wheel Arch gap at required points is measured . Here minimum value 10 mm is only at SB and at all other section it is less than 10 mm.

According to the data the car doesnot pass the European standard.