Related Experiment Video
Updated: May 29, 2026
09:17
Experimental Investigation of the Flow Structure over a Delta Wing Via Flow Visualization Methods
Published on: April 23, 2018
An accelerating inverted wing with ground effect: downforce measurement and reconstruction.
Shanwei Zhou1, Edwin F J Overmars1, Jerry Westerweel1
1Laboratory for Aero & Hydrodynamics, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands.
Experiments in Fluids
|May 28, 2026
Summary
This study measured downforce on an inverted wing near the ground. Lower ground clearance during acceleration increases downforce, with wake effects becoming significant later.
Area of Science:
- Aerodynamics
- Fluid Mechanics
- Automotive Engineering
Background:
- Understanding ground effect aerodynamics is crucial for vehicle performance.
- Inverted wings are key components in generating downforce for stability and grip.
Purpose of the Study:
- To experimentally measure downforce generated by an inverted wing under ground effect.
- To analyze the influence of accelerating and steady motion on downforce.
- To investigate the role of flow structures in downforce generation.
Main Methods:
- High-speed planar particle image velocimetry (PIV) to capture flow fields.
- Multi-body impulse-based method for downforce reconstruction from PIV data.
- Analysis of lift coefficient contours to understand flow structure contributions.
Main Results:
- Lower ground clearance significantly enhances downforce during acceleration, attributed to the suction side boundary layer.
- Flow separation occurs post-acceleration, with the wake region becoming a major contributor to downforce.
- Dynamic motion phases (acceleration vs. steady state) exhibit distinct downforce characteristics.
Conclusions:
- Ground clearance and motion dynamics are critical parameters for optimizing downforce.
- Wake structures play a vital role in sustained downforce generation.
- Findings offer insights for aerodynamic design improvements, particularly relevant to Formula 1 racing.
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