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Since, the auxiliary function F 1(æ) for the water-saturated
part of the reservoir will be equal to zero, so when using graphs to
assess the oil extraction and water content in the well production,
we pre-determine the value:

V
F 
    1t       i , (5.11)

w
b
i
r
o
1
Q i (t )
where: (1-ρ r o–ρ b w) – amount of water that entered to the
formation; F 1( ) ∞ – value of function F 1( ), when æ ;
V i – the volume of pore space, which is located between the
sections of i-row and i-1-row; Q i(t) – the total amount of water that
entered the formation from the start of development and till the
time t.
Using equation (5.11), we will determine the next value:
F 
Q ( t)  1      
 i  r o b w 1     t . (5.12)
V i i
Then we define left part of equation as τ:
Q ( t)   , (5.13)
i
V i
which in turn means the multiplicity of washing, in other words he
ratio of the pumped volume of water to the pore volume.
While taking into account the multiplicity of washing and
dependence (5.12), the graphic dependencies of n w(æ), η(æ) now
are rebuilt depending on τ. The plots of n w(τ), η(τ) shown on Fig.
5.6.
By calculated values of τ and using graphic dependencies,
we can write the equation of disconnection of series of wells:
Q i(t) + Q i+1(t)+ Q i+2(t) = Q' i(t) + Q' i+1(t)+ Q' i+2(t), (5.14)
where the left side – oil flow rates of well rows in the end of i-
stage, the wright side – oil flow rates of well rows at the beginning
of i+1 stage.

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