A Perturbation Solution for Bingham-Plastic Mudflows

Publisher Website
Google Scholar
Abstract
An analytical solution is proposed for laminar mudflows and debris flows that can be modeled by a Bingham-plastic law. Two-dimensional, unsteady, nonuniform, Bingham flows released from a point source or a source of finite size (dam-break problem or mudslide problem) on a steep slope are considered. The method of matched asymptotic expansions was implemented to get a first-order solution. For the dam-break problem, the proposed model is found to be valid when the shock wave has advanced three reservoir lengths downstream. Also, it is found that the Bingham flow only propagates a finite distance downstream, with the shock depth asymptotically approaching the yield depth and the shock velocity asymptotically falling to zero. The hydrograph produced by a Bingham flow is seen to have a slower and lower flood peak and a longer and higher flow tail than that produced by Newtonian flow having the same dynamic viscosity. Comparison of the model predictions with laboratory observations shows reasonable agreement.

This publication has 16 references indexed in Scilit: