Capillary Pressure- Saturation Relationship

The capillary pressure-saturation relationship describes how the pressure needed to move a wetting fluid through small spaces (pores) in a material changes as the amount of that fluid increases. When the pores are mostly filled with the wetting fluid, the pressure needed to displace it is higher; as the pores fill with more fluid, the pressure decreases. This relationship helps us understand how fluids like water and oil move through soils or rocks, influencing fields like groundwater flow, oil recovery, and soil science by showing how saturation levels affect fluid movement.