Two different methods were applied to determine the permeability:
The absolute permeability (kabs, [m², Darcy]) of gas was determined by a singlephase
experiment with a sandstone as dry sample (LxBxH) shown in figure 1. With
this steady state method a constant confining pressure of 4 bar was induced. At the
upstream side a gas (air) pressure up to 1.5 bar was created.
The gas volume was measured at the downstream side with the soap bubbles: The
velocities of the rising
bubbles were
measured in the brine.
Out of this the “bubble”
volume the gas flow
can be determined. [...]
Table of Contents
I. Introduction: Measurement Principle
II. Darcy's law for compressible media
III. Darcy's law for incompressible media
IV. Error propagation and Standard Deviation
V. Conclusion
VI. References
Objectives and Topics
This laboratory report aims to determine the permeability of various sandstone samples using two distinct experimental approaches: one designed for compressible media (gas) and another for incompressible media (water), while quantifying experimental accuracy through error propagation analysis.
- Measurement of gas permeability using steady-state methods and Klinkenberg correction.
- Analysis of water permeability for incompressible flow conditions.
- Application of Darcy’s Law to calculate permeability coefficients.
- Evaluation of experimental errors, including standard deviation and instrument inaccuracy.
- Assessment of the Klinkenberg effect on gas flow through porous media.
Excerpt from the Book
I. Introduction: Measurement Principle
Two different methods were applied to determine the permeability: The absolute permeability (kabs, [m², Darcy]) of gas was determined by a single-phase experiment with a sandstone as dry sample (LxBxH) shown in figure 1. With this steady state method a constant confining pressure of 4 bar was induced. At the upstream side a gas (air) pressure up to 1.5 bar was created.
The gas volume was measured at the downstream side with the soap bubbles: The velocities of the rising bubbles were measured in the brine. Out of this the “bubble” volume the gas flow can be determined. With Darcy’s law for compressible media and the Klinkenberg correction the absolute permeability can be calculated. The temperature is supposed to be constant by about 25°C.
Summary of Chapters
I. Introduction: Measurement Principle: Outlines the dual-method approach for determining permeability using gas for compressible media and water for incompressible media under controlled pressures.
II. Darcy's law for compressible media: Details the calculation of absolute permeability for specific samples based on pressure measurements and the application of the Klinkenberg correction.
III. Darcy's law for incompressible media: Describes the experimental setup for measuring permeability using water, including the parameters and conditions required for the calculation.
IV. Error propagation and Standard Deviation: Explains the mathematical methodology used to quantify experimental uncertainties and errors associated with the laboratory measurements.
V. Conclusion: Evaluates the experimental results, discusses observed deviations from expectations, and identifies potential error sources like pressure fluctuations and measurement inaccuracies.
VI. References: Provides the source of the laboratory course guidelines used for this study.
Keywords
Permeability, Darcy's Law, Klinkenberg Effect, Sandstone, Compressible Media, Incompressible Media, Porosity, Flow Rate, Flux, Error Propagation, Standard Deviation, Petrophysics, Laboratory Experiment, Pressure Measurement
Frequently Asked Questions
What is the primary focus of this laboratory report?
The report focuses on determining the absolute permeability of sandstone samples using specific experimental setups for both compressible and incompressible fluids.
What are the central themes discussed in the paper?
The central themes include fluid dynamics in porous media, the application of Darcy’s Law, the Klinkenberg effect in gas experiments, and rigorous error analysis.
What is the main objective of the research?
The objective is to calculate permeability coefficients and assess the accuracy of experimental measurements through error propagation and standard deviation calculations.
Which scientific methods are applied in this work?
The work employs steady-state flow experiments using soap bubble volume measurements for gas and burette volume measurements for water.
What topics are covered in the main body?
The main body covers the theoretical basis of Darcy's Law for different media, the presentation of experimental data (samples 47-3, 26-3, 29-3), and the mathematical evaluation of measurement errors.
Which keywords best describe this study?
Key terms include permeability, Darcy’s Law, Klinkenberg effect, petrophysics, and experimental error analysis.
How is the Klinkenberg effect handled in the gas experiment?
The Klinkenberg effect is calculated by plotting permeability against the inverse of mean pressure to adjust for gas slippage effects.
Why are there discrepancies in the results for sample 47-3?
Discrepancies are attributed to high porosity, potential pressure leakage in the apparatus, and human error during time measurements.
How does the measurement of water permeability differ from gas?
Water permeability is measured using an incompressible steady-state apparatus where flow is determined by volume over time through a saturated sample, without a Klinkenberg correction.
- Citar trabajo
- Amalia Aventurin (Autor), 2013, Permeability, Múnich, GRIN Verlag, https://www.grin.com/document/272604
