Alert Circle

This page is not compatible with Internet Explorer.

For security reasons, we recommend that you use an up-to-date browser, such as Microsoft Edge, Google Chrome, Safari, or Mozilla Firefox.

Note on browser support

Capillary Pressure Simulation

with VGSTUDIO MAX

Simulate capillary pressure directly on CT scans of different materials (e.g., porous or composite materials) using the Capillary Pressure Module, which is part of Transport Phenomena Simulation Module for VGSTUDIO MAX.

Simulation of Capillary Pressure

The simulation of capillary pressure can be used to determine characteristics of scanned porous materials, for example in geosciences to characterize soil and rock samples. 

The Capillary Pressure Module: 

  • Computes quantities like the pore size distribution and the capillary pressure drainage curve for a scanned porous material sample.
  • Works directly on voxel data and makes use of the sub-voxel accurate, local adaptive surface determination in VGSTUDIO MAX.

Pore Size Distribution

The pore size distribution is calculated using the approach of maximal inscribed spheres. The software uses spheres of varying size as probes and attempts to fit them into the pore space. For each point, the largest fitting sphere overlapping this point is found. The diameter of that sphere is assigned to this point as the local pore diameter.

Capillary Pressure Drainage Curve

For determining the capillary pressure curve, the software simulates a quasi-static drainage experiment. The sample is connected to two fluid reservoirs, a wetting phase (WP) and a non-wetting phase (NWP) reservoir, at user-defined sections of the volume boundary. The pore space is initially filled with WP. The pressure in the NWP reservoir is increased in discrete steps, resulting in injection of NWP into the pore space.

Three different test setups can be mimicked by defining the reservoir boundaries for WP and NWP according to the casesa) Tempe cell, b) porous plate setup, and c) mercury injection experiment.

Results

The Transport Phenomena Simulation Module provides four overlays for the visualization of the results in 2D and 3D: 

  • pore diameter
  • isolated pore space
  • non-wetting phase front
  • trapped wetting phase

Pore Diameter

The pore diameter is the diameter of the largest inscribed sphere.

Pore diameter
Isolated pore space

Isolated Pore Space

The isolated pore space is the pore space that is not connected to either WP or NWP reservoir.

Non-Wetting Phase Front

The non-wetting phase front is the space occupied by the NWP at a certain user-specified pressure.

Non-wetting phase front
Trapped wetting phase

Trapped Wetting Phase

The trapped wetting phase shows portions of the WP which are isolated from the WP reservoir. These portions are regarded to be trapped forming the residual WP.

Additional Results

Pore diameter histograms can be visualized. The porosity and the capillary pressure can be viewed as curve plots along a line connecting the WP and NWP reservoir planes in the normal direction. The capillary pressure curve displays the capillary pressure in relation to the WP saturation. 

All curves can be easily exported using the .csv format.

The pore size is shown as a histogram plot.

Benefits

Easy to use

  • No simulation expertise required
  • No meshing required

 

Efficient

  • Seamless workflow from material segmentation to simulation in one software

Realistic

  • All microstructural details are captured by a subvoxel accurate surface determination