EXPERIMENTS ON ENTRY OF A ROUGH CIRCULAR CYLINDER INTO WATER. APPLICATIONS TO RAINSPLASH EROSION OF SOIL

J. C. Wells, M.F. Walter
1999 PROCEEDINGS OF HYDRAULIC ENGINEERING  
Pressures generated during the initial moments of vertical entry of a circular cylinder (10.1cm radius) into a water bath at 10 m/s were measured near the water surface by 2.5 mm diameter pressure transducers mounted in the sidewalls of an impact chamber, at distances of 0,1,2, and 3 cm from the centerline. The incompressible theory of water entry agrees very closely with results for a smooth projectile. The theory is also found to apply to drop impact on a surface during this initial phase.
more » ... s initial phase. Results are also presented for projectiles roughened by a fixed layer of beads . The presence of a bead layer whose thickness is 5% of the projectile radius drastically reduces the peak pressure , from 55 bar for a smooth projectile to about 20 bar. The decrease in peak pressure should not influence the amount of soil eroded during impact, which depends more critically on the extent of the region of stresses that exceed the soil's shear strength.
doi:10.2208/prohe.43.785 fatcat:2ih4pzuwofgejg3asws2ubo2hm