Models used to calculate the speedup

There are two models that are going to be studied here. A 2D model of
a profile, and a 3D model. The 2D profile is plotted on the following picture
:
Avbp uses n processors by splitting the mesh into n parts, each processor
having a part to compute on. Since they have to send the boundary data
of their part to other processors, it is very important to split the mesh
minimizing the number of boundary elements. To do this three algorithms
can be used :
an optimization using the elements coordinates
an optimisation weighting each cell according to its size
an optimisation using a complicated algorithm
Using four processors, the first method gives : (There is one color
for each processor)
The second one :
and the third one :
A zoom on the central prt shows the location of the 4th zone :