DEVICE FOR ACOUSTIC STIMULATION OF OIL AND GAS-BEARING FORMATION Russian patent published in 2002 - IPC

FIELD: oil and gas producing industry; applicable in oil recovery. SUBSTANCE: device has downhole instrument whose lower part accommodates two and more acoustic radiators communicating with ambient medium through instrument body windows. Each radiator has two reflectors in the form of cone installed coaxially, with one radiator on each side of radiator end. Cone height equals radiator radius, with an angle of 90 deg at top facing radiator. Distance d between ends of neighboring conical reflectors amounts from 2 mm to 10% of reflector height. Distance A from radiator end face to reflector top is selecled from conditions of maximum transmission of average power into formation and is calculated by formula A = nλ/8-R, where n=1, 5, 9.. .; λ is acoustic wave length; R is internal radius of well pipe. Each acoustic radiator is formed by two identical piezopacks with length equalling 1/4 of sound wave in material of piezoelectric element having common immovable base for their fastening, which is located between piezopacks. Extreme piezoelectric elements of piezopacks have the same polarity. EFFECT: increased efficiency and productivity of oil recovery. 3 dwg