Abstract

Using a finite element calculation, this study seeks to evaluate the effects of sipes on the transient behavior of viscous hydroplaning: fluid pressure distribution, fluid film thickness, and descending velocity as a function of time. From calculations on block‐type tread elements with open or closed sipes, sipes in the low velocity region in the thin fluid film have been shown to be very effective in controlling the occurrence of viscous hydroplaning. Application of the transient analysis procedure to rib‐type tread elements showed that highly zigzagged tread elements with a sipe at the line of symmetry are more effective for traction on wet pavement. Results from the study provide qualitative and quantitative guidelines to tire designers in the search for the optimum pattern of individual tread elements on the basis of thin film wet traction.