Fender Design - Wheel Arch Challenge

Hi colleagues,

In this challenge I should report about Fender requirements and requested regulations as well as Wheelarch design.

One of first important tasks for fender is to protect a engine of car against little piece of stones on the road that are hitting on the vehicle.It protect also pedestrians for stones’ hitting and against mud and liquids on the road.So,I have opened parts got in Challenge – Wheel arch calculation.

There are various types of fenders but basicaly there are always same mounting places for mounting it as Body,Sill,Pillarr,Drip and Cowl.Body and Drip areas could be defined as a major parts for mounting Fenders.Mounting is done with fasteners and there are special regulations especialy for a Drip area.Drip could be defined as a area on Fenders where are holes for jointing Fenders on Body chassis.

When we are designing Drip area,it is important to have a minimum 200mm space for a Cowl area on back of the fender (where we are having wipers instaled and plastic for protecting car’s inside from outside weather and outer circumstances (rain,cold weather etc.) and at least 150mm on front of the Fender – Head lamp area.So,on the Fender the area between that space could be used for a Drip area to fasten a Fender to Hood.During Fender design,there are also some rules and regulations that should be obeyed to have a satisfying Fender that could fulfill your requirements and could be manufactured.

There are also some regulations that should be considered regarding outer design and appearnace of the Fender, such as Height of the Fender – approximately 80mm (and Height of the Drip area is approximately 40mm as previously said).With a slope of 45deg on the outer side of the Fender,the front distance of Fender from slope is 40-50mm (should be less than 50mm to be able to produce the part).

Wheelarch Design

To have a proper protection inside the car engine compartement and pedestrians there are some regulations for Wheelarch compartement.By Wheelarch design it is important to measure distance or clearence between Tire and Fender in the K Area.

K Area is defined as shown on images bellow.There are various regulations regarding K Area and Wheelarch in USA,Japan or EU standards.There are different regulations in World because it depends on different road conditions in every Country and average measures of the passangers.If outer line of Fender could not fulfill requirements of clearence design team should be appionted to that area in order to change curvature of Fender.

By Japan standards geometrical relations that define K Area is shown on image.Clearence L must be greater than 5mm in the K Area.Japan regulations are given on image bellow,when we have constructed points A,B and C,then we are pulling lines vertical to those points in Z direction and then clearance between Tire and Fender on so constructed lines should be 5mm or more.

European regulations are a little bit different.K Area is defined as on image.We have angles 30deg and 50deg as on Japan standard but here is added a point on 150mm distance from Wheel centre.Between that point – SE and point SC we are constructed a point SD on simetry line.At all sections SA-SB,SB-SC,SC-SD and SD-SE clearence should be greater then 10mm.Very important change here is that clearence is defined with at least 10mm.

K Area by USA regulations are also defined a littke bit different as shown on image,but clearance L is as by Japan standard, 5mm.K Area is defined as shown on image from +100deg to -100deg.L clearance is defined as before,on points on Fender that are intersecting lines under various angles.Lines are then drawn in Z direction and distance from Tire must be 5mm or more.It should be inspected also under 30deg forwards and 50deg backwards as previously and check a clearance.

As a part of challenge I should check if those Fender and Tire are fullfiling EU Regulations.That is why I have on previously made lines/sketch for EU regulations I have drawn a surface as shown.

Then I have measured distance of intersection points to the Tire.

As it can be seen,distance is in all critical areas for EU Regulations more than 10mm,that means Fender is good designed regarding Wheelarch requirements.

In order to be sure by Wheelarch design we take 10mm clearence under various K Areas.If there should be changes Styling team should be contacted.Drip Area and Wheelarch Area are major factors by designing Fender.

Sometimes on Front Fender are rubber parts installed to reduce noise and vibrations of the car.

Thank you for taking time to read these lines in Fender/Wheelarch design challenge.

Best regards,

Ivan Tole