Sidewall Protrusion Geometry in Pneumatic Tires for Drag Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing pneumatic tires do not adequately reduce air resistance at high speeds, despite previous designs that incorporated protrusion portions to enhance airflow, as there is a continued demand for improved performance in this area.
Innovation Solution
The pneumatic tire features protrusion portions with external contours having multiple main external contour portions of different curvatures and connection portions, which generate a vortex and promote turbulent flow, reducing air resistance by suppressing the bulge of air separating from the vehicle's tire housing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If protrusion portions are provided on the tire side portion to reduce air resistance, then air resistance is reduced, but the air resistance reduction effect is insufficient for further performance improvement
Solution Approach 1:
The protrusion portions are designed with specific curved external contours including a first curved portion, second curved portion, and third curved portion. These curved surfaces guide airflow smoothly around the tire side portion, reducing turbulence and drag. The curvature radii are specifically controlled (first curved portion: 0.5-2.0mm, second curved portion: 1.0-3.0mm, third curved portion: 1.5-4.0mm) to optimize flow separation and reattachment, achieving superior air resistance reduction compared to linear or angular protrusion designs.
2Object-affected harmful factors
If the external contour includes multiple main external contour portions with different curvatures and connection portions, then airflow is further promoted and air resistance is reduced, but the manufacturing complexity increases
Solution Approach 1:
The external contour of the protrusion portions is segmented into distinct functional zones: a first curved portion for initial flow guidance, a second curved portion for flow acceleration, a third curved portion for flow reattachment, and connection portions linking these segments. This segmentation allows each portion to perform its specific aerodynamic function optimally while maintaining overall integration. The segmented design enables precise control of flow separation and reattachment points, achieving significant air resistance reduction despite the increased geometric complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design significantly improves air resistance reduction, enhances fuel economy, and reduces lift, thereby improving driving performance and steering stability by promoting airflow and minimizing stagnation.
Implementation Method 1
generate a vortex and promote turbulent flow
Implementation Method 2
promote turbulent flow
Data Source
AI summary
A pneumatic tire includes a plurality of protrusion portions extending along a tire side surface of a tire side portion longitudinally intersecting a tire circumferential direction or a tire radial direction and being provided at intervals in the tire circumferential direction, and each of the protrusion portions includes an external contour that includes a plurality of main external contour portions having different curvatures, and a connection portion connecting between the main external contour portions, the external contour projecting from the tire side surface in a cross-sectional shape in a longitudinal direction.