Dynamic measurement of the fluid pressure in the tire contact area on wet roads

The main goal of this study was the experimental investigation of the fluid pressure in the boundary region between wet grip and hydroplaning. In order to gain an insight into the processes in the tire contact area, a test setup was developed to directly measure the fluid pressure in the water film between tire and road. The fluid pressure was measured on an asphalt track for different speeds, water heights and tire patterns on an inner drum test bench. The influence of the examined parameters on the fluid pressure is clearly visible and physically plausible. Braking tests were done in order to clarify how much the fluid pressure build up influences the overall braking performance in the boundary region between wet grip and hydroplaning.