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4
2  3
R k    , 1 05  .
2 
Thus, hydrodynamic calculations are made only for one
well and the results apply to all wells.
Hydrodynamic calculations for solution gas drive more
difficult and less accurate than in the case of homogeneous oil
through that phase permeability are not defined sufficiently
precisely and calculations due to the difficulty of differential
equations of motion based on approximate methods.
Oil recovery factor under the solution gas drive is
calculated using the pressure dependency of oil saturation
 i k b  
P
  1 0 , (3.46)
 0 b  
P
i k
where  0 and b(Р 0) – initial oil saturation and volume formation
factor under saturation pressure;  k i and b(Р k і) - oil saturation and
volume formation factor under average pressure.
Final oil recovery factor depends on the properties of the
formation of oil and gas, from the amount of gas dissolved in oil,
and also the phase permeability. However, in all cases, the final oil
recovery factor under solution gas drive is lower than the water
drive.
Solution gas drive characterized by a rapid drop in the
formation pressure over time and increase the gas-oil ratio which
at some stage of development reaches a maximum and then begins
to decrease as a result of exhaustion and complete decontamination
of field. Without action on the artificial reservoir, the drive is
ineffective. However, in the initial period of development wells
flowing, though not a long time. No water in production wells.
For solution gas drive of development dynamics of
development depending on the time is shown in Fig. 3.16.

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