Experimental investigation on single-phase non-linear flow in low permeability cores

Abstract

The saturated seepage curves with the single-phase of the standard brine and kerosene in the low permeability full diameter core plugs from the Erdos basin have been measured through fully automatic flooding system - AFS300 ™ provided by Core Lab of America under low pressure gradient(0.005~0.300 MPa/m) with the steady state approach. Through the BP-100 air spring back to pressure valve, core outlet pressure is controlled. The experimental results indicate that the outlet flow rate of core plugs increases linearly with the increase of pressure gradient; and the phenomena of threshold pressure gradient and non-linearity are not observed in terms of saturated flow method. Moreover, obvious threshold pressure gradient is not observed in terms of unsteady state method. Single-phase non-linear flow in low permeability cores with Newtonian fluids-brine and kerosene meets Darcy law. The interaction force between the surface of pore and the standard brine and kerosene can not cause non-linearity and threshold pressure gradient of single-phase flow.