A Low Cost Rolling Road for Tire Measurements in a Small Eiffel Wind Tunnel 2017-01-1504
Wind tunnel aerodynamic testing involving rolling road tire conditions can be expensive and complex to set up. Low cost rolling road testing can be implemented in a 0.3m2 Eiffel wind tunnel by modifying a horizontal belt sander to function as a moving road. This sander is equipped with steel supports to hold a steel plate against the bottom of the wind tunnel to stabilize the entire test section. These supports are bolted directly into the sander frame to ensure minimal vibrational losses or errors during testing. The wind tunnel design at the beginning of the project was encased in a wooden box which was removed to allow easier access to the test section for installation of the rolling road assembly. The tunnel was also modified to allow observers to view the testing process from various angles. These wind tunnel modifications include replacing the wooden panels with clear Lexan plastic sheets, adding dampening material into the test section connections, and making an easily interchangeable test piece in the side of the tunnel for quick experimental changes. The tire axle assembly, designed to hold the tire as it freely rotates on the sander belt, records the various forces acting on the wheel. The wind tunnel stinger uses a steel airfoil cross section with a ball joint pivot to transfer the forces and moments to load cells aligned with the desired force directions. The load cells are calibrated and forces measured using a LabVIEW computer system and force comparisons are made with a static tire under the same wind conditions to help determine differences between static tire testing and dynamic tire testing.