ABSTRACT
The horizontal and vertical balance of forces and the balance of momentum let to get the following differential system (Fig. 3):
dn dx
y= - ′σ τ (1)
dt dx
hy y= ′- ′ +γ σ τ( ) (2)
dm dx
n ty= - ′ (3)
where:
t = µn; m = nB; h = x - y tanα
being µ a constant. Basic convention: from now onwards all the
developments will be done adimensionally. To achieve this the dimensional measuring units in Table 1 are adopted:
Having solved any problem the real results would have to be obtained by multiplying them by the respective physical units.