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the pressure losses of water, which is pumped into the reservoir.
Represented P inj .
In general, the amount of water injected is determined
Q inj=Q sel + Q los, (4.1)
where Q sel – the amount of fluids (oil + water), which are selected;
Q los – loss of water that escapes the contour.
Q sel determined by hydrodynamic calculations. Q los
depends on the pressure at the line injection wells and the average
reservoir pressure in the aquifer of the reservoir.
Depending on the values of pressure at the line injection
and the average reservoir pressure for the contour of the reservoir
are three cases:
1) If P line > P f , then the water pumped flows into the
aquifer area. In this case Q inj= Q sel + Q los. It is necessary to take
into account the elastic properties of the reservoir and fluid out the
line injection.
2) If P line < P f , then Q inj= Q sel - Q los. This case is rarely
used in practice.
3) When P line = P f no loss of water and Q los = 0. This case is
used most often. In this case, the impact of external area
completely isolated and reservoir works due to the energy of water
injection. In this case, water is injected into injection wells
completely used to displacement oil.
In the literature suggested many formulas for
determination Q los, one of which is
kBh Р line  Р f
Q  , (4.2)
los
 w 3 t 
where B - the length of injection line, m;  - piezoconductivity
2
factor, m /sec; t – the period of time, sec; µ w - coefficient of
dynamic viscosity of water (µ w = 1 mPa·s).
To assess the degree of compensation selections of fluids
from the reservoir injected water introduce the concept of factor

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