Numerical Study of Effects of Air Dam on the Flow Field and Pressure Distribution of a Passenger Car

Everything that is attached to the outside of the vehicle to improve the driving performance of the vehicle by changing the flow characteristics of the surrounding air or to pursue the external personality is called a tuning part. Typical tuning components include front or rear air dam, also known as spoilers, splitter, and side air dam. Particularly, the front air dam prevents the airflow flowing into the lower portion of the vehicle and increases the amount of air flow to the side and front of the vehicle body, thereby reducing lift force generation that lifts the vehicle body, and thus, improving the steering and driving performance of the vehicle. The purpose of this study was to investigate the role of anterior air dam in the flow around a sedan passenger car using computational fluid dynamics. The effects of flow velocity, trajectory of fluid particles on static pressure distribution and pressure distribution on body surface were investigated by varying flow velocity and size of air dam. As a result, it has been confirmed that the front air dam improves the flow characteristics, thereby reducing the generation of lift force of the vehicle, so it helps in steering and driving characteristics.

• Min Ye Koo
• Ji Ho Ahn
• Byung Il You
• Gyo Woo Lee

• Numerical study
• computational fluid dynamics
• air dam
• tuning parts
• drag
• lift force.

[1] N. Roberts, “Air dams, splitters, spoilers and wings – downforce increases grip, grip decreases lap times, and isn’t that the whole point?”, https://nasaspeed.news/tech/aero, May 1, 2013.
[2] A. Damle, A. Magdum, and I. Tikekar, “Effect of air-dam on low end passenger cars”, International Journal of Recent Engineering Research and Development (IJRERD), vol. 1(8), pp. 9-15, 2016.
[3] A. L. Browne, N. L. Johnson, H. Muhammad, and J. Brown, “Shape memory alloy actuated vertical deploy air dam: Part 1 — Performance requirements and design” ASME 2012 Conference on Smart Materials, Adaptive Structures and Intelligent Systems, vol. 2: Mechanics and Behavior of Active Materials; Integrated System Design and Implementation; Bio-Inspired Materials and Systems; Energy Harvesting, Stone Mountain, Georgia, USA, September 19–21, 2012.
[4] S. McBeath, “Airdams - Often present, potentially very beneficial, but frequently misunderstood, we explain how airdams work”, Racecar Engineering, pp. 93–94, October 2004.
[5] D. Mitra, “Effect of relative wind on notch back car with add-on parts”, International Journal of Engineering Science and Technology, vol.2(4), pp. 472-476, 2010.
[6] V. N. Kumar, K. L. Narayan, L. N. V. N. Rao, and Y. S. Ram, “Investigation of drag and lift forces over the profile of car with rear spoiler using CFD”, International Journal of Science and Research, vol. 4(9), pp.1298-1304, 2013.
[7] M. Z. Ali, S. Khan, N. Mohan, and P. Mandape, “Aerodynamics”, pp. 64-67, 2014.