Modeling River Ice Using Discrete Particle Simulation

摘要

Recent advances in discrete element modeling now allow the direct simulation of river ice dynamics. By resolving the contact and body forces acting on thousands of individual floes at each time step, the initiation, grounding, and formation of river ice jams can be simulated and studied. The attendant water flow is modeled using a coupled unsteady hydraulic model, with feedback provided between floes and water by water drag and blockage of the channel flow area by ice. The regimes of water flow that are modeled include open-channel flow with no ice, flow under moving or stationary ice, and high-Reynolds-number porous flow through grounded and floating ice masses. The use of variable channel geometry, which allows realistic channel sections to be modeled, is described here. Results are presented for a simulation of the arrest of a large ice run by an ice-control structure consisting of nine evenly spaced, cylindrical piers. Discrete element simulation promises to be an important tool in the design and implementation of ice-control measures.