Fully Coupled Model of Ice-Jam Dynamics

This paper presents a numerical model that simulates the dynamic failure and reformation of an ice jam. The model comprises a simultaneous solution of the 1D, unsteady flow equations (conservation of mass and momentum) for water flow and ice motion. Its use is demonstrated in the routing of flow hydrographs through a channel containing an initial jam or accumulation of broken ice. The model shows the extent to which changes in flow discharge may affect profiles of jam thickness and flow depth for these situations. It also shows how ice momentum may affect the jam-thickness profile. Dimensionless parameters, characterizing initial jam stability and the shape of the hydrograph, are identified to indicate conditions when changes in flow discharge and ice momentum should be taken into account when estimating jam thickness.