国外某大学石油工程系油藏工程考试试题.pdf

Course:- 28117 Class:- 289013 HERIOT-WATT UNIVERSITY DEPARTMENT OF PETROLEUM ENGINEERING Examination for the Degree of MEng in Petroleum Engineering Reservoir Engineering 1 Tuesday 6th January 1998 09.30 - 13.30 NOTES FOR CANDIDATES 1.This is a Closed Book Examination. 2.15 minutes reading time is provided from 09.15 - 09.30. 3.Examination Papers will be marked anonymously. See separate instructions for completion of Script Book front covers and attachment of loose pages. Do not write your name on any loose pages which are submitted as part of your answer. 4.This Paper consists of 3 Sections:- A, B and C. 5.Section A:-Attempt all Questions Sections B here balanced production implies that the rate from a layer is proportional to its thickness i.e. q1 /h1 = q2 /h2 . This is the basis of “smart” wells used to optimise production behaviour. Each choke diameter may be continuously varied from fully open to closed. Given a vertical lift curve for the well i.e. a plot of bottom-hole flowing prerssure, pwf , versus well total flow-rate, q , where q = q1 + q2 , show how the choke settings may be calculated to give maximum balanced production. Assume that the choke performance is given by an equation of the form: qi = Cch At 2p 1 2 where p = pressure drop over choke qi = flow-rate through device Cch = discharge coefficient (constant) At = throat area = D2 t /4 = Dt Dp Dt = throat diameter Dp = pipe diameter 20 C15Describe the phenomenon of “supercharging” and the procedures which may be used to obtain a useful WFT survey in a low permeability reservoir 20 End of Paper q q = q1 + q2 q1 p1S1 Layer 1 Layer 2 k1 h1 p2k2 h2S2 q2 Balanced Production Using Variable Chokes Q14 0 1.0 1.1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.25 1.1 1.0 0.9 1.0 1.05 1.05 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.2 2.4 2.6 3.0 3.0 2.8 1.2 1.3 1.1 1.1 0.95 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.9 12345678 789101112131415 Compressibility of Natural Gases (Jan. 1, 1941) BEHAVIOUR OF OIL FIELD HYDROCARBON SYSTEMS Compressibility Factor, z Pseudo Reduced Temperature Pseudo Reduced Pressure, Pr 3.0 2.8 2.6 2.4 2.2 2.0 1.9 1.8 1.7 1.6 1.5 1.45 1.35 1.4 1.