CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing

Erhan Fırat; Mehmet Seyhan

doi:10.30939/ijastech..1941954

CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing

Abstract

A numerical investigation was conducted to examine the flow around a European tractor-trailer combination model (GETS) using a steady RANS model k-ω SST at a Reynolds number of 100000. Experimental aerodynamic force measurements were also carried out for the purpose of validating the CFD simulations. The present paper focuses on the effect of steady blowing from the thin slots positioned on the rear surface (base) of the model on the aerodynamic characteristics of the GETS. The combination of three key parameters was tested: the jet-to-freestream velocity ratio (VR), the inclination angle of the jet (θ), and the jet’s location. More than 100 CFD simulations were performed over a range of key parameters. The findings indicate that the jet direction’s inclination towards the rear surface typically leads to a modest yet favorable effect on the drag reduction. It has been demonstrated that increasing the VR to 2 has the potential to reduce aerodynamic drag by up to 50%. However, it is also demonstrated that employing VR values greater than approximately 1.25 is not viable in terms of active flow control efficiency. At θ=0°, the active control efficiency of the both-jets configuration is approximately 6 for VR=0.5 and approximately 1.6 for VR=1. The total drag coefficient on the model is reduced by 8.3% and 17.7% for the VR=0.5 and 1 cases, respectively. It has been demonstrated that the viscous components of total drag and lift are independent of jet configuration, VR, and θ. In both upper and lower jet configurations, it is possible to increase or decrease the aerodynamic lift acting on the model by changing the inclination angle.

Keywords

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Details

Primary Language

English

Subjects

Automotive Engineering (Other)

Journal Section

Research Article

Authors

Erhan Fırat ^*
0000-0003-2800-6714
Türkiye

Mehmet Seyhan
0000-0002-5927-9128
Türkiye

Publication Date

June 11, 2026

Submission Date

May 1, 2026

Acceptance Date

June 9, 2026

Published in Issue

Year 2026 Volume: 10 Number: 2

DOI

https://doi.org/10.30939/ijastech..1941954

IZ

https://izlik.org/JA26SP27AK

Cite

RIS / Bibtex

APA

Fırat, E., & Seyhan, M. (2026). CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing. International Journal of Automotive Science And Technology, 10(2), 411-426. https://doi.org/10.30939/ijastech..1941954

AMA

1.Fırat E, Seyhan M. CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing. IJASTECH. 2026;10(2):411-426. doi:10.30939/ijastech.1941954

Chicago

Fırat, Erhan, and Mehmet Seyhan. 2026. “CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model With Steady Base Blowing”. International Journal of Automotive Science And Technology 10 (2): 411-26. https://doi.org/10.30939/ijastech. 1941954.

EndNote

Fırat E, Seyhan M (June 1, 2026) CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing. International Journal of Automotive Science And Technology 10 2 411–426.

IEEE

[1]E. Fırat and M. Seyhan, “CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing”, IJASTECH, vol. 10, no. 2, pp. 411–426, June 2026, doi: 10.30939/ijastech..1941954.

ISNAD

Fırat, Erhan - Seyhan, Mehmet. “CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model With Steady Base Blowing”. International Journal of Automotive Science And Technology 10/2 (June 1, 2026): 411-426. https://doi.org/10.30939/ijastech. 1941954.

JAMA

1.Fırat E, Seyhan M. CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing. IJASTECH. 2026;10:411–426.

MLA

Fırat, Erhan, and Mehmet Seyhan. “CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model With Steady Base Blowing”. International Journal of Automotive Science And Technology, vol. 10, no. 2, June 2026, pp. 411-26, doi:10.30939/ijastech. 1941954.

Vancouver

1.Erhan Fırat, Mehmet Seyhan. CFD Simulation of Aerodynamic Forces on a Simplified Heavy Vehicle Model with Steady Base Blowing. IJASTECH. 2026 Jun. 1;10(2):411-26. doi:10.30939/ijastech. 1941954