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#
Case when surface tension and
difference of density are not absent

Phenomenons of difference of density and surface tension are known as to
stabilize the flow.
Now, at the interface we don't have equality of pressure because of
surface tension:

is the value of surface tension between the two fluids.
In Bernoulli equation hydrostatic term
(i=1 or 2) must be introduced.

Like in the last section we have a condition of stability by saying
the determinant of the matrix of the system is equal to zero:

with
and .

*Stephanie Terrade*

*Julien Delbove*

*2000-11-06*