Dynamic impact of steep waves against a vertical wall
MetadataShow full item record
Recent experiments carried out at the University of Trento show that a liquid-granular surge impacts against a vertical wall according to two different mechanisms: if the wave front is sufficiently fast the flow is totally deviated in the vertical direction forming a vertical jet-like bulge, while if it is relatively slow it is totally reflected by the wall. Most of the theoretical approaches presented in literature for the analysis of the dynamic impact of a debris surge against an obstacle consider only the second mechanism described above. The impact force in this case is obtained from the mass and momentum balances applied to the reflected bore under the hypothesis of homogeneous fluid. The application of this scheme to the jet-like impact leads to a significant underestimation of the impact. We present an analysis of the formation of the vertical bulge, which is usually observed for Froude numbers larger than one, and propose a new analytical expression to estimate the dynamic impact forces also in this situation. The analytical expressions we propose are in a reasonable agreement with the experimental results.