Displacement efficiency defines the fraction of the initial pore-saturating fluid displaced in a the piston sweep by invaded fluid
E_D = 1- \frac{V_{FLUID, \ INITITAL} - V_{FLUID, \ INVADED}}{V_{FLUID, \ INITITAL}}
Displacement efficiency defines the fraction of the initial pore-saturating fluid displaced in a the piston sweep by invaded fluid
E_D = 1- \frac{V_{FLUID, \ INITITAL} - V_{FLUID, \ INVADED}}{V_{FLUID, \ INITITAL}}