Tkacik, P., Carpenter, Z., Gholston, A., Cobb, B. et al., "A Low Cost Rolling Road for Conducting Flow Measurements around a Tire in a Small Eiffel Wind Tunnel," SAE Technical Paper 2017-01-1504, 2017.
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 cast iron 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. This assembly uses an airfoil section on a ball joint pivot to transfer the moments to load cells aligned with the desired force directions. The load cells are calibrated before testing with various known weights outputting a voltage value to establish a weight to strain ratio. The testing forces are then processed in LabVIEW and compared to forces on a static tire under the same wind conditions. This comparison displays the experimental differences in accuracy between static tire testing and dynamic tire testing.