05. FENDER DESIGN - WHEEL ARCH CHALLENGE

1. Introduction about Wheel Arch:

Wheel Arch is the semi-circular part of the fender positioned above the wheel of the vehicle. The design of Wheel arch of a fender should be such that it must shield wheels and protect both passengers compartment and pedestrians from projection of water, mud and stones. For the vehicle to get the use permit in different countries, the wheel arch of fenders must be comply with the standards and regulations set by the respective countries.

2. Objective of this Wheel Arch Challenge:

To calculate the wheel arch area and to prove if the given fender of car will pass the European standards or not.

• European Standards for Wheel Arch:
• 

• Conditions To Satisfy European Standards: -

  1. The clearances are as shown in above fig. at all the five sections SA-SA, SB-SB, SC-SC, SD-SD and SE-SE must be greater than 10 mm.
  2. For Wheel Guard Requirement The value of ‘a’ shall be more than 5 mm at a line 30° forward and 50° rearward from centre vertical axis of the wheel.
• STEPS
• To draw a 2d sketch initially we took a plane at top face of the wheel as reference and 2d Sketch is drawn on the wheel face as per the European standards as shown in above fig.
• A horizontal and vertical Axis is drawn from the centre of the wheel.
• The vertical axis intersection point is named as SA. Similar references are drawn at 30 degrees to the left and 50 degrees to the right of the section SA and are named SB and SC respectively.
• A line of 150mm is drawn perpendicular to the horizontal axis and the normal from that point on the fender gives us SE.
• The midpoint of the arc cut by the sections SC and SE gives a new section SD with the help of derived curves in sketch.
• The value of 'L' at each section and the value of ‘a’ are found out to determine whether the fender satisfies the European standards as shown below.
• provided and projected on the wheel arch at sections SA, SB, SC, SD and SE to measure 'L', ‘a’ and wheel arch area.

1. Obtaining the values of clearance "L"
2. a) To Measure "L" for the given wheel and fender at SB:

The value of "L"(SB)=10.00mm

b) Measuring "L"(SA)

The value of "L"(SA) =9.949mm

c) Measuring "L"(SC), "L"(SD), "L"(SE):

The values of "L"(SC), "L"(SD), "L"(SE) are 0.1126, 2.8468, 5.9018mm respectively.

TABLE A: Clearance "L" obtained at sections SA, SB, SC, SD and SE

Section	Clearance "L" 10(in mm)	Comments
SA	9.949<10	Fail
SB	10<=10	Pass
SC	0.1126<10	Fail
SD	2.8468<10	Fail
SE	5.9018<10	Fail

From table A, the given fender does not pass the European Standards for the Wheel arc area at sections SA, SC, SD and SE

B) To Measure clearance "a" for wheel Guard Requirements

a) Finding the values of "a" at line 30 degree forward from centre vertical axis of the wheel.

Here value of "a" at line 30 degree forward from centre vertical axis of the wheel is =43.6263mm

b) Finding the value of "a" at line 50-degree rearward from centre vertical axis of the wheel.

Here value of "a" at line 50-degree rearward from centre vertical axis of the wheel is=38.3597mm

TABLE B: Clearance Value "a" obtained at SB & SC

Section	Angle (in degree)	Clearance	Comments
SB	30	43.6263>5	Pass
SC	50	38.3597>5	Pass

From this table B, the given fender passes the European standards for wheel arch area only in the case of clearance "a"

Measurement of Face Area of the wheel arch:

Using measure face command and single face selection filter we easily got the Face area of the wheel arch = 24432.9334 mm2

Conclusion:

From the above results we can conclude that the given fender doesn't pass the European Standards for Wheel Arch Area.