Effects of Acoustic Stimulation on Fluid Flow in Porous Media

Abstract

Acoustic waves are mechanical waves that can be generated via vibrations. The use of such waves for enhancing flow and transport in porous media has some advantages over traditional enhanced recovery methods including eliminating bypassing effects and environmental hazards. Many physical mechanisms have been identified to improve recovery by applying an acoustic wave. However, the relative contributions of different mechanisms to the stimulated flow and transport phenomena are not still well understood. There are also uncertainties regarding the effects of important controlling factors such as frequency or the efficiency of different source coupling methods. In this work, a multiphysics model is developed to address the latter issues and propose a criterion to distinguish different regimes of acoustically induced effects. Simulation results of this model are correlated to the recovery enhancements to provide the required applied stress or supplied energy that causes observable changes in fluid flow behavior under laboratory conditions. A loss number of N l is proposed based on the dimensionless analysis of wave equation in fluids where the most energy dissipation occurs. The critical values of N l are obtained by implementing a classifier machine learning algorithm on a data set from the literature. When N l is less than 2.1 × 10 −7 , the recovery enhancement is expected to be caused by mechanical effects, and therefore lower frequency (seismic) waves are favorable. At an N l greater than 10 −6 , however, higher frequency (ultrasonic) waves are preferred since the changes in flow behavior are triggered by the adsorbed acoustic energy. In seismic excitations, coupling the source to the pore fluid gives the highest performance, while in ultrasonic treatments, the maximum viscosity reduction can be achieved when a transient frequency scenario is adopted. The results of this study give a better understanding of mechanisms behind the effect of acoustic wave application in porous media.

Postprocessing of tungsten carbide‐nickel preforms fabricated via binder jetting of sintered‐agglomerated powder

“…Two methods were used to measure the densities of coupons after being intermediately sintered and HIP'ed: the geometric approach 48 and the Archimedes approach (ASTM C20) 49 . In the geometric approach, the mass of the prism, measured using a Fisher Scientific SLF103 scale with an accuracy of .001 g, is divided by its volume, measured with a Vinca DCLA‐0605 digital caliper that has a resolution of .01 mm.…”

Pore Pressure Diffusion Waves Transmission in Oil Reservoir

“…During seismic excitation, more energy can be directed toward the slow waves through poreflowing coupling. The propagation of slow P-waves cannot be applied for deeper target formations based on estimations of penetration depth, which is significantly less than a meter [56,57]. However, it was predicted that seismic waves could penetrate regions with low permeability and highly heterogeneous reservoir formations that conventional oil recovery techniques could not easily access [52,53,58,59].…”

The effect of NaCl and HPAM solution concentration on HPAM gel structure degradation by ultrasonic waves

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