01-Flow Regimes and the Diagnostic Plot

# 01-Flow Regimes and the Diagnostic Plot - Flow Regimes and...

This preview shows pages 1–7. Sign up to view the full content.

Flow Regimes and the Diagnostic Plot 1

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Flow Regimes and the Diagnostic Plot 2 Upon completion of this section, the student should be able to: 1. Identify the early, middle, and late time regions on a diagnostic plot. 2. Identify the following flow regimes from their characteristic shape on a diagnostic plot: volumetric/PSS/recharge behavior, radial flow, linear flow, bilinear flow, spherical flow. 3. List 3 things that may affect the pressure response during the early time region. 4. List 3 types of boundaries that may affect the pressure response during the late time region.
Flow Regimes and the Diagnostic Plot 3 The diagnostic plot is a log-log plot of pressure change and pressure derivative on the vertical axis vs. test time on the horizontal axis. The pressure derivative is defined as the derivative of pressure with respect to the natural logarithm of time. • Pressure change vs. time – Flow test - – Buildup test - • Pressure derivative – Change in pressure per unit fractional change in time – Mathematically, – Has units of pressure, can be plotted together with pressure on same graph wf i p p p - = ( 29 0 t p p p wf ws = - = ( 29 t ln p t p t =

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Flow Regimes and the Diagnostic Plot 4 Early-time region: wellbore and near-wellbore effects. These effects include wellbore storage, skin factor, partial penetration, phase redistribution, and finite- and infinite-conductivity hydraulic fractures. Middle time region: infinite-acting reservoir behavior. A homogeneous reservoir will give a horizontal derivative response during the middle time region. Data during this region provide the best estimate of reservoir permeability. Late-time region: boundary effects. There are a large number of different types of boundaries that may affect the pressure response, including sealing faults, closed reservoirs, and gas/water, oil/water, and gas/oil contacts.
Flow Regimes and the Diagnostic Plot 5 Common geometric shapes occur in many different reservoir models A single reservoir model may exhibit different flow patterns at different times - Flow regimes occur in a specific sequence for a given model Flow Regimes - Volumetric behavior - Radial flow - Linear flow - Bilinear flow - Spherical flow

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Flow Regimes and the Diagnostic Plot 6 Volumetric behavior occurs when the wellbore, the reservoir, or part of the reservoir acts like a tank. Perhaps the most common occurrence of volumetric behavior is in wellbore storage, although
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/05/2011 for the course PETE 689 taught by Professor Staff during the Spring '08 term at Texas A&M.

### Page1 / 31

01-Flow Regimes and the Diagnostic Plot - Flow Regimes and...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online