Based on Previous Research to Improve the Rear Wing of the Car

Shuai Ou

and Haichuan Sun

Institut Hohai-Lille, Hohai University, Nanjing, 210000, China

Shanghai Leighton School, Shanghai, 200231, China

Keywords: Rear Wing, Drag Force, Downforce.

Abstract: Previous studies have found that drag and down force generated by Formula cars’ rear wings, as well as the

whole car’s aerodynamics can be changed with different speeds, different Angles of Attack, different types

of rear wings, and different install locations. This study filtered and organized those articles. After using

principles and logical assumptions to analyze. This study also studied how the rear wing shape of a Formula

car can change its downforce and drag; beyond that, the first part of the suggestion on how to modify the rear

wing shape was given. Furthermore, the second part of the suggestion was given after combined with real

race speed. Lastly, based on the different impacts on the aerodynamic characteristics, a suggestion on how to

improve the shape and install location of the rear wing to make the best downforce and drag ratio on Model

Drela AG03, makes the driving experience and aerodynamic characteristics better.

1 INTRODUCTION

Formula 1, one of the top sports in the world, has the

most development in car performance. Car engineers

consider most on how to make their cars go fastest

when designing those machines. Studies across the

globe have shown that race car speed isn’t heavily

relied on the engine, but on its grip. When the

tangential force applied on tires and ground goes

beyond a certain limit, the tire will lose its grip and

eventually spin. (Wang, Zhang, and Zhou, 2021) This

is because driving force, steering force, and brake

force in conventional race cars is made in the friction

force within the tire and the ground. Nowadays, the

best way to increase downforce and grip without

adding extra weight is to use the rear wing’s

aerodynamic design. (Zhang, Li, and Qiu, 2021）

Countless studies about the whole race car have

shown that while the car weight brings 20% of its

grip, the rear wing can generate 80%. (Zhu, and Yu,

2020) Downforce directly shows how much the rear

wing can provide grip; meanwhile, drag shows how

much the rear wing shape can change the car driving

experience. Therefore, finding the balance between

those two figures is the key to making and designing

an excellent race car.

https://orcid.org/0009-0008-3645-3155

https://orcid.org/0009-0003-5721-5811

Rear wing shapes have a direct and significant

impact on downforce and drag. It can improve

handling and stability by scientific design and

modification while reducing the impact on drag as

little as possible. This research will summarize

factors that affect by rear wing and different rear wing

choices and designs based on rear wing shape design

and research on previous studies; Furthermore, this

research combined and modified the rear wing

design. This research can make new and more choices

for single-rear wing race cars, make contributions for

better handling and stability, and as fast as it can.

2 THEORETICAL BASIS

Racing cars are usually subjected to lateral,

longitudinal, and vertical resistance during driving.

Installing a racing spoiler can reduce resistance on the

racing car and increase downforce (Wang, and Xia,

2021). According to Bernoulli's equation, it can get:

(Zhang, Jiang, and Gong, 2022). When the upper

surface speed of the racing spoiler is less than that of

the lower surface, the air pressure difference will be

generated, so as to generate downforce under

pressure.

480

Ou, S. and Sun, H.

Based on Previous Research to Improve the Rear Wing of the Car.

DOI: 10.5220/0013422300004558

Paper published under CC license (CC BY-NC-ND 4.0)

In Proceedings of the 1st International Conference on Modern Logistics and Supply Chain Management (MLSCM 2024), pages 480-483

ISBN: 978-989-758-738-2

Figure 1: Drela AG03 model diagram.

R The studied racing spoiler in this research is a

single racing spoiler. Among the foreign researchers,

Riebeek investigated the effect of spoiler and car

body interaction on the general shape of two closed-

wheel racing cars in his research. Later, they

combined 3D computer simulation techniques with

wind tunnel testing during the aerodynamic

development of closed-wheel racing cars

(1994)(Kieffer, Moujaes, and Armbya, 2006),

conducted experimental and computational studies of

ground effects on two-dimensional spoilers(Mather,

Papadakis, and Heron, 1998), and experimented and

tested a variety of spoiler configurations in Wichita

State University's Beech Memorial low-speed wind

tunnel. According to Zhidong Guo's spoiler research

on the Drela AG series in 2023, speed, spoiler type,

and elevation have an impact on the downforce and

resistance of the racing spoiler. When conducting

experiments on different spoilers, under the condition

that speed and elevation were determined, the

resistance and down force were generated by different

types of spoilers. The results showed that Drela AG03

has the highest ratio of downforce and resistance in

figure 1, so it was considered to have the best

aerodynamic performance. Therefore, Drela AG03

was taken as the basis of this design and was upgraded

and improved.

3 RESULTS

In the process of studying the influence of speed on

the downforce and resistance of a racing spoiler, it

was found that the higher the speed, the higher the

maximum and minimum pressure on the spoiler, and

the higher the resistance and downforce caused by the

spoiler(Guo, 2022). It was also found that the ratio of

the spoiler resistance and downforce was the best

when the speed was 60m/s. In the process of studying

the influence of the angle of attack on spoiler

resistance and downforce, it was found that the

greater the spoiler angle of attract, the greater the

resistance, but the downforce showed a Z-shape

distribution and reached the peak at 20°. In addition,

under different driving speeds, the angle-XY pressure

image obtained by changing the angle of attack of the

racing car was the same, that is, when the angle of

attack was about 20°, the ratio of downforce and

resistance was the largest, and the racing car could

obtain the best driving experience at this time.

Therefore, it is concluded that the optimal operating

parameters of the spoiler during the driving process

should be: Drela AG03(flat spoiler bottom) spoiler,

driving speed: 60m/s, and angle of attack: about 20°.

However, for the general FI racing cars, in reality,

the cornering speed is at least 300km/h, about

83.33m/s. To achieve the best downforce and

resistance of the racing spoiler, and the best stability

of the car, it is necessary to make certain adjustments

to the spoiler. According to the simulation data, when

the speed, when the speed is 83.33m/s, the downforce

is smaller than the resistance, so it is necessary to

improve the spoiler to make the ratio of downforce

and resistance close to 11.03. According to the

research, the spoiler angle of attack was changed at

the speed of 80m/s, it was found that the ratio of

downforce and resistance at 20°was the largest, so the

front part of the spoiler can be appropriately raised to

form an angle difference of nearly 20°with the back

part.

Based on Previous Research to Improve the Rear Wing of the Car

481

Figure 2: Different positions of the spoiler.

Figure 3: Spoiler design diagram.

In the study of the interaction between the spoiler

and the aerodynamic characteristics of the car body,

Zhang Yingchao et al. conducted a simulation test of

the influence of the spoiler on the overall

aerodynamic characteristics of the car body at three

different typical installed positions of the spoiler in

the Figure. The top one of Figure 2 is position 1,

below it, is position 2, and the far left one is position

3. (Yan, Du, and Hu, 2019). It was found that when

the spoiler was installed in position 3, relatively far

away from the car body, although the downforce of

the spoiler was reduced more than that of the single

tail and positions 1 and 2, and the lift-resistance ratio

was also poor, the life force of the spoiler was

improved compared with positions 1 and 2; the

downforce of the diffuser and the bottom plate was

greatly increased; finally, the overall downforce and

life-resistance ratio were relatively optimal.(Katz,

and Dykstra, 1994) The optimal operation of the

racing cars can be enhanced based on the experiment

verification, the overall analysis of the forces of the

specific steering mechanism of the racing cars, and

the racking track conditions.

On the basis of the above analysis and

organization, the following better-improved single

racing spoiler was designed, as shown in Figure 3.

The spoiler installation position is position 3

mentioned above, which is the position 10 cm down

and 10 cm back of the normal position for the spoiler

installation of normal Fi racing cars.

4 DISCUSSION

For better handling performance when the car goes

through a corner at high speed, according to the

Bernoulli equation, the improved rear wing of the car

in this study can provide better stability within the

optimal range of the ratio of rear wing resistance to

downforce, and has almost no impact on the speed of

MLSCM 2024 - International Conference on Modern Logistics and Supply Chain Management

482

the car. The improvement of this study mainly lies in

enlarging the height difference between the front and

back parts of the tail fins, and even eliminating the

elevation adjustment device of the tail fins, which can

further the lightweight of the car and provide new

ideas for the future lightweight research of the car.

This study can also provide a new idea for the study

of the rear wing position of the car. It is not necessary

to follow the rules and adopt the position this research

have always used. The aerodynamic characteristics of

multiple positions can be tested to make the

aerodynamic performance of the car more excellent

and make the car faster.

5 CONCLUSIONS

This study first researched the impact of the rear wing

shape on the downforce and drag with the existing

race car aerodynamics theory. Based on that, the

Authors gave the first part of how to modify the rear

wing; then combined with real-life speed factor to

give the second part of the modification. Lastly, after

examining the different changes of aerodynamic

characteristics in different positions of the rear wing,

the final suggestion of rear wing shape and install

location was given, position 3, which is 10

centimeters down and 10 centimeters back from the

normal F1 car’s rear wing installed.This research is

aimed to improve on part of single rear wing in race

car, and expanded on more, like the design of car

body, engine, tires and so on. Hopefully, futuristic

studies can have more improvements on more factors.

By focusing on these elements, researchers push the

boundaries of what is possible in race car engineering.

AUTHORS CONTRIBUTION

All the authors contributed equally and their names

were listed in alphabetical order.

REFERENCES

Guo, Z., 2022. Numerical Simulation Study of Drag and

Downforce on the Rear Wing of F1 Cars. In 2022 2nd

International Confe. on Computer Technology and

Media Convergence Design (CTMCD 2022). Atlantis

Press, pp. 632-645.

Katz, J., Dykstra, L., 1994. Application of Computational

Methods to the Aerodynamic Development of

Prototype Racing Cars. Society of Automotive

Engineers, SAE Paper 942498, Warrendale, PA.

Kieffer, W., Moujaes, S., Armbya, N., 2006. CFD Study of

Section Characteristics of Formula Mazda Race Car

Wings. Mathematical and Computer Modelling, 43(11-

12), pp.1275-1287.

Mather, R., Papadakis, M., Heron, I., 1998. Gurney Flap

Experiments on Airfoil, Wing, and Reflective Plane

Models. Journal of Aeronautical Industry, 35(2).

Wang, D., Zhang, G., Zhou, F., et al., 2021. Research on

Design and Performance of Student Equation Active

Pneumatic Balancing Device. Proceedings of the

Annual Meeting of China Automotive Engineering

Society.

Wang, Y., Xia, Y., et al., 2021. FSAR Racing Car Front

Wing Optimization Design. Proceedings of the Annual

Meeting of China Automotive Engineering Society.

Yan, Z., Du, C., Hu, Y., et al., 2019. Research on Tail

Aerodynamic Performance of Formula SAE Car based

on Finite Element Method. Journal of Chongqing

University, 42(4), pp.1000-5820.

Zhang, F., Li, C., Qiu, Y., 2021. CFD Simulation Research

and Analysis of Intelligent Adjustment Tail of Racing

Car. Proceedings of the Annual Meeting of China

Automotive Engineering Society.

Zhang, Y., Jiang, Q., Gong, H., et al., 2022. Interaction

between Rear Wing and Body Aerodynamic

Characteristics of a Racing Car. Proceedings of the

Academic Annual Meeting of the Automotive

Aerodynamics Branch of the China Society of

Automotive Engineering 2022 – Pneumatic Sub-conf.

State Key Laboratory of Automotive Simulation and

Control, Jilin University

Zhu, J., Yu, S., 2020. FSAE Racing Spoiler Shape

Optimization. China Automotive Engineering Society

Annual Meeting.

Based on Previous Research to Improve the Rear Wing of the Car

483