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The procedure is the following calculations.
The whole interval of possible changes in the value of
formation pressure is divided into small spaces. To ensure high
accuracy of set pressure interval and P k і and P k i+1 equal to 0.1-0.2
MPa. Practice shows that the smaller the interval between the
commitments and values P k і and P k i+1, the more precisely
determined depending (Р). In some cases, the amount of pressure
P k і -P k i+1 and can be increased and make 0.5-1.0 MPa. Then, set
the initial value for the first interval oil saturation calculation (it is
1). From tables, Tsarevich determines Tsarevich function ( k і)
and for the graphics dependency of oil and gas properties define
the parameters S, b, z, under appropriate pressures.
Table Tsarevich are as follows:
 F oil() F gas()
1 0 1

Then determine the gas-oil factor formula (3.33) and the
formula (3/32) determine oil saturation at the end of the selected
interval pressure changes. Then move to the next interval changes
in pressure, where the initial oil saturation serving predefined
value.
As a result of these calculations get graphic dependence
(Fig. 3.15).

3.3.2 Definition of flowrates, bottom-hole pressures
under solution gas drive

The task is solved for two cases:
1) Q(t)=const;
2) Р вh= const.

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