Energy transfer in a liquid filled elemental passage of a porous medium for permeability enhancement due to pulsations of a vapor bubble
In this paper, a novel method which has been proposed during the last decade for increasing of the permeability of porous media of petroleum reservoirs by transferring of energy via ultrasound waves is investigated numerically. Increasing of permeability of porous media of petroleum reservoirs results in enhancing of oil recovery. This technique is based on the idea of transferring of energy to the liquid filled porous media via the ultrasound waves and consequently producing of pulsating vapor bubbles. The generated vapor bubbles transfer the energy of ultrasound waves in the liquid filled passages of a porous medium through velocity and pressure fields in the liquid domain and in turn apply impact forces on obstacles which have been made from accumulation of clays inside passages of the porous medium around the wellbore of an oil well after a long operating time. Removing of these obstacles, results in increasing of permeability of the porous medium and enhancing of oil recovery. The boundary integral equation technique is employed for numerical simulation of the growth and collapse of the cavitation bubbles and transferring of energy in the liquid domain by the bubbles pulsations. Three different geometries have been proposed as elemental passages of a porous medium. Numerical results show that the controlled growth and collapse of vapor bubbles induced by emission of the ultrasound waves in a liquid filled porous medium could lead to a powerful technology for enhancing oil recovery and consequently for industrial and economical development of the nations and countries having petroleum and other liquid reservoirs.