This preview shows pages 1–2. Sign up to view the full content.
PGE 323
Final Examination
Open Notes
May 12, 2008
Pope
1.
A slight generalization of the standard Black Oil equations allows for the oil pseudo
component to partition between the gas and the oil phases in addition to the usual
partitioning of the gas pseudo component between the gas and oil phases. By analogy to
R
s
in SCF of gas per STB of oil, we can define r
o
in STB oil per SCF of gas. Both
depend on pressure and temperature. This is called the modified Black Oil model and is
used by reservoir engineers worldwide when they use Black Oil reservoir simulators.
This makes the Black Oil model equivalent to a standard pressurecomposition diagram
for a binary hydrocarbon mixture at reservoir temperature such as you studied in
thermodynamics where the two components might have been methane and nheptane.
(a) 10% Derive a mass balance on the oil pseudo component for the modified Black Oil
model defined above.
Assume threephase flow of oil, gas and water in a one
dimensional, linear reservoir with no mass transfer of the hydrocarbons to the water
phase.
(b) 5% Insert Darcy's law in the appropriate form into the mass balance for the oil pseudo
component to get the modified Black Oil diffusivity equation.
(c) 5% List all of the assumptions needed to derive the diffusivity equation in part (b).
Indicate yes or no whether the following were assumed to derive it: incompressible fluids
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview. Sign up
to
access the rest of the document.
This note was uploaded on 05/15/2011 for the course PGE 323 L taught by Professor Johns during the Spring '10 term at University of Texas at Austin.
 Spring '10
 Johns

Click to edit the document details