[Andy Chen]

Dear experts:

When I use sediment scour model. We need set up about sediment parameter(ex:diameter, density, critical shield number, and maximum packing fraction et al.). I have read user's manual, but I still do not understand what is maximum packing fraction. What will happen about result If I set 0 or 1.

Thanks your help!!

[JBurnham]

Maximum packing fraction is the fraction (volume of all sediment species/open volume in cell) of sediment at which the cell becomes 'packed' and the drag function in the cell goes to infinity (no flow). It is equal to (1 - porosity). 0.64 is the default and has been analytically demonstrated for uniformly-sized randomly-packed spheres. Sand is typically of porosity 0.3 to 0.45, so max packing fraction of 0.55 - 0.7.