Pore Occupancy Analysis (poreXtractor):

In this GitHub repository, you will find the code that enables the quantification of pore and throat occupancy in a 3D micro-CT image. The code processes pore network data extracted from dry scan images using a dedicated pore network extraction algorithm. Subsequently, the wet image is mapped onto the extracted network. Please note that the preferred format for wet images is raw or TIFF. This code generates the mapping results and provides the distribution of pores and throats based on the input data. This code allows you to perform detailed pore occupancy analysis on wet micro-CT images of porous media. The primary features include:

• Dominant Phase Identification: The code identifies and signals the dominant phase within each pore and throat. This data is crucial for deciphering fluid distribution and flow behavior in your porous media.

• Pore and Throat Size Distributions for Specific Phases: The code creates distribution charts for pores and throats that contain a specific phase. These charts are plotted against pore and throat radii, offering a clear visual representation of phase distribution in your porous media. It's worth mentioning that both volume-weighted and frequency-based types of distributions can be generated. Tabulated data is also provided for further analysis.

• Overall Pore and Throat Distributions: In addition to specific phase distributions, the code also provides distribution results for all pores and throats within the extracted network. Both volume-weighted and frequency-based types of distributions can be generated. This information is useful for comprehensive network analysis and comparisons between different networks.

• Isolated Pore and Throat Distributions: In addition to the overall pore and throat distributions, the code also provides distribution results for isolated pores and throats within the extracted network. Again, both volume-weighted and frequency-based types of distributions can be generated. These distributions represent elements that are not connected to the inlet or outlet via the resolved pore space.

Required Repository

To use this code, you first need to perform pore network extraction. To familiarize yourself with the network extraction process from dry scans, please check out the pnextract repository.

Standalone Software (poreXtractor)

Included in the repository is a windows-based standalone software inside the bin.zip file, which simplifies the entire process. This standalone software does not require any dependencies. A sample porous media file is provided for you to test the software and familiarize yourself with its functionality.

Usage

To utilize this software effectively, please follow these steps:

1. The input image for network extraction should be a segmented dry-scan image, which can be in raw, raw.gz, or TIF format. It must be an 8-bit image, where zero represents pores, and one represents the rest. For larger images, the use of raw.gz format is recommended.

2. Once you have selected the dry-scan image, you will be prompted to enter image details, including size (Nx * Ny * Nz) and voxel size. The code will automatically insert the image size and voxel size into the MHD file based on the information you provide.

3. To perform the pore occupancy analysis of two-phase flow images (wet images), please ensure that they are in raw or TIF format and are in 8-bit.

By following these steps, you'll ensure compatibility with our software.

Note: The provided sample porous media has dimensions of 500x500x500 and a voxel size of 2.75 microns.

Citing our Work

If you find this code and poreXtractor standalone software useful and use it in your research or project, please consider citing the following papers that describe the underlying methods and models:

1. Foroughi, Sajjad, et al. "Pore-by-pore modeling, analysis, and prediction of two-phase flow in mixed-wet rocks." Physical Review E 102.2 (2020): 023302.

2. Foroughi, Sajjad, Branko Bijeljic, and Martin J. Blunt. "Pore-by-pore modelling, validation and prediction of waterflooding in oil-wet rocks using dynamic synchrotron data." Transport in Porous Media 138.2 (2021): 285-308.

Additionally, pnextract is based on these references:

3. Dong, Hu, and Martin J. Blunt. "Pore-network extraction from micro-computerized-tomography images." Physical review E 80.3 (2009): 036307.

4. Raeini, Ali Q., Branko Bijeljic, and Martin J. Blunt. "Generalized network modeling: Network extraction as a coarse-scale discretization of the void space of porous media." Physical Review E 96.1 (2017): 013312.

By citing our work, you will help others to understand the foundation of this code and contribute to the recognition of our research efforts.

Contact and References

If you encounter any issues or have suggestions for improvement, please feel free to raise an issue or submit a pull request. For contacts and references please see: https://www.imperial.ac.uk/earth-science/research/research-groups/pore-scale-modelling or contact Sajjad Foroughi, email: s.foroughi@imperial.ac.uk or foroughi.sajad@gmail.com