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Tire Water Splash
Dragos Moroianu Volvo Cars Corporation Andreas Blixt FS Dynamics
Overview
• Background
• Model description
• Results
• Implementation
• Conclusion
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Background
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• What is splash?
• Why is splash a problem?
• Current splash CAE method description
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What is splash
• Speed between 30-65km/h
• Water depth 20-80mm
• Higher depth... Wading
• Even higher depth ... submarine
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• To protect pedestrians from water
What is the problem with splash?
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What is really the problem with splash?
• Engine bay water contamination
• High water loads on critical components
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Experiments
provide qualitative
information
Numerical (DPM) - hard to estimate
trajectory after wall interaction
Background – Current approach
Numerical (DPM) - hard to estimate
trajectory after wall interaction
Experiments
provide qualitative
information
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Side Splashing
a
w
Model Description
Forward Splashing
b
w
D
4D
11D
3D
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Model Description
• Incompressible flow
• Multiphase (liquid/gas) - VOF
• Large Eddy Simulation
• Smagorinsky subgridscale model
• Polyhedral mesh
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Model Description
• Velocity inlet gas: 8.3 m/s
• Velocity inlet liquid: 8.3 m/s; 50 mm thickness
• Symmetry plane
• Pressure outlet
• Moving wall – translation on ground with 8.3 m/s; rotation on wheel with ~25 rad/s
• Cell size – tire surface 1.25 mm, volume characteristic edge 5 mm, max. 40 mm
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D
4D
11D
3D
Results Results monitoring point
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Water tire splash of an isolated wheel
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Splash – front view
Water tire splash of an isolated wheel
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Splash – top view
Water tire splash of an isolated wheel
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Splash – side view
Water tire splash of an isolated wheel
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Splash - view from underneath
Water tire splash of an isolated wheel
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Splash – rear view
Example of Implementation
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Conclusion
• Good frequency agreement with experiments
• Good qualitative agreement with experiments
• More work is needed for a robust procedure
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Questions?
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