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where a and b - approximation coefficients that are constant for a
given oil and gas at a certain pressure.
There are two methods for determining coefficients a and
b:
1) dependencies on graphics;
2) analytically.
To do this, we write the equation (6) for two values of P kі
and P k i+1

 
 F  i k
oil
      аР i k  ;b
  oil Р i k b Р i k
  (3.38)
 F oil  i k 1
  Р  Рb   аР i k 1  .b
 oil i k 1 i k 1
Solving system of equations (3.38) determine the
coefficients a and b. For this equation deducted from the first
second. We have
 
F  i k F oil   i k 1 
oil

      Р  Рb 
b
Р
Р
a  oil i k i k oil  i k 1  i k 1 .
P i k  P  i k 1
From the first equation defines the coefficient b
 
F 
b  oil i k  aP , or
 oil     i k
b
Р
Р
i k
i k
 
F  i k F oil  i k  1 
oil

 
F        Р  Рb 
Р
b
Р
b  oil i k  oil i k i k oil i k  1 i k  1 P .
 oil     P  P i k  1 i k
Р
Р
b
i k
i k
i k
There is another oil inflow equation
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