Abstract
The rheology of submerged granular flows is described according to a heuristic model recently proposed by Armanini et al. (2014), which is a single parameter model, based on the fundamental evidence that the collisional and the frictional regimes coexist across the flow depth. The main novelty of the heuristic model is to provide an equation of state valid also for the frictional regime. Investigations on the role of the drag force in the balances of uniform submerged granular flows are presented. A new relation of the voidage function valid for all the values of concentration is derived.