Fender Design - Wheel Arch Challenge
01) Objectives
*) To calculate wheel arch area for given wheel & fender and to verify whether it passes the european standards or not.
02) Introduction
*) The wheel arch is the semicircular part positioned above the wheel of a vehicle. It covers the wheel & It helps in restricting the mud or any other particles to thrown into the the engine or car chamber.
*) FENDER
Fender is a part of a vehicle which frames a wheel and prevents from entering sticky and hard substance such as mud, sand, rock, etc. into the air. 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. Hence fender helps to prevent the matrial to throw into the air.
*) Types of fenders
- Full Bumper type
Full bumper type fenders which cover whole wheel are seen in most of the old model cars because currently all the cars are using half bumper type fenders to avoid scrap while manufacturing.
2. Half Bumper type
Currently all the car models uses half bumper type fenders, the advantage of using half bumper type is, it reduces the cost of manufacturing al the tool size reduces & also reduces the overall weight of the vehicle, which ultimately increases vehicle performance.
*) Minimum clearance should maintain between the Wheel and the arc area to avaid collision between them during suspension.
*) Hence to ensure this the wheel should be positioned little inside the fender.
03) European regulation standard for wheel arc area
*) As per european regulation standards the min. clearance between the outermost ends of the wheel & the fender should be 10mm.
*) measure the ckearance L value at all the five positions i,e @ SA, SB, SC, SD & SE.
*) At all the position the clearance L value should be above 10mm to satisfy tyhe european regulations.
*) The below image shows the points where we should verify the clearance value.
04) Wheel arc calculation
*) Claculate the wheel arc for given Wheel & fender
*) Draw sketch lines by taing wheel outer surface as the sketch support.
*) First draw verical line from the center axis (SA).
*) Draw line at an angle of 30° forward (SB) & 50° rearward (SC) from the central verticle axis.
*) Also draw a line passing through the point which is at a distance of 150mm from horizontal axis on fender (SE).
*) Draw another line exactly in between SC & SE linee i,e SD.
*) Calculate the clearance L at specified points
| Posiotion / Line | Min. Clearance Value (in mm) | Actual Clearance Value (in mm) |
| SA | 10 | 9.949 |
| SB | 10 | 10 |
| SC | 10 | 0.114 |
| SD | 10 | 1.651 |
| SE | 10 | 3.297 |
*) The above table indicates the clearance value for the wheel arc at differnt position.
*) The only posion is clearing the european standard is SB, rest all the values are below minimum value.
*) Hence a proposal should be made to change the design of Fender as per the regulation standards.
05) Conclusion
*) The given wheel & fender are verified for the Wheel arc clearance value as per european regulation standards, and it is not meeting the standards value, hence proposal for fender design change should be made.