1. Bifurcation Mechanics
Conjecture: The network is in dynamic equilibrium because these asymmetric bifurcations are in dynamic equilibrium
What processes?
flow partitioning by bed topography and channel planform
flow partitioning by downstream water surface BCs
flow partitioning by secondary circulation
bedload partitioning by bed topography
suspended load partitioning by tapping surface waters
Consider simplest case with lengths and downstream WSE of branches equal, and steady Q and Qs of main stem
Perfectly symmetric case seems like a reasonable solution
What about asymmetric cases? Maybe, if…
topographic steering of bedload: bed ramp partitions bedload according to long and transverse slopes
shallower throat taps water with lower suspended solids
bed ramp creates dynamic WSE differences at throats, thereby changing energy slopes in branches
topographic steering of flow
Method: Use morphodynamic model simulating Unsteady/Nonuniform flow and sed transport: Delt3d (SLIDE showing grid with BCs and verbal list of relations)