Impact of Active Turbulence Generation System in 3/4 Open-Jet Wind Tunnel: Flow Structures, Shear Layer, and Low-Frequency Fluctuations
Paper i proceeding, 2025

With increasing attention to complex aerodynamic conditions such as crosswinds, gusts, road turbulence, and vehicle drafting, accurately reconstructing these unsteady and turbulent environments in automotive wind tunnels has become a significant challenge. Addressing this challenge is crucial for broadening experimental conditions and advancing research in unsteady aerodynamics. However, the integration of turbulence generation systems impacts low-frequency fluctuation phenomena, leading to pressure and velocity inaccuracy, and also affects the flow structure in the test section as well, especially in the jet shear layer. In this paper, the impact of an active turbulence generation system on turbulence characteristics and flow structures within jet shear layer in a wind tunnel is numerically investigated. By comparing the flow structure among the empty wind tunnel, and wind tunnel with static and dynamic active turbulence generation system, the mechanisms underlying these configurations are analyzed. In addition, low-frequency fluctuations with the presence of active turbulence generation system are compared to those observed in the empty wind tunnel. The results indicate that while the turbulence generation system effectively produces the desired turbulent components, it also increases the non-uniformity of the jet shear layer, and hence intensifies low-frequency fluctuations in the test section.

wind tunnel

Turbulence generation system

shear layer

low-frequency fluctuations

Författare

Qing Jia

Tongji University

Lanwei Qin

Tongji University

Civil Zhao

Tongji University

Yikun Wang

Tongji University

Chao Xia

Chalmers, Mekanik och maritima vetenskaper, Fordonsteknik och autonoma system

Zhigang Yang

Tongji University

Huanxia Wei

Tongji University

SAE Technical Papers

01487191 (ISSN) 26883627 (eISSN)

2025 SAE World Congress Experience, WCX 2025
Detroit, USA,

Ämneskategorier (SSIF 2025)

Strömningsmekanik

Farkost och rymdteknik

DOI

10.4271/2025-01-8783

Mer information

Senast uppdaterat

2025-06-26