Abstract: A method is described for recovery of a hydrocarbon fluid from a porous medium by injection of a fluid into the porous medium. The method includes determining a Rayleigh time on the basis of the density of the fluid and the hydrocarbon fluid, the median pore diameter of the porous medium, and surface tension between the fluid and the hydrocarbon fluid. The method includes arranging a chamber in fluid communication with the porous medium via at least one conduit, and having the chamber comprising first and second wall parts movable relative to each other. The pressure stimulation includes providing an impact pressure in the fluid to propagate to the porous medium via the conduit, wherein the impact pressure is generated by the collision process between an object arranged outside of the fluid and the first wall parts for the first wall part to impact on the fluid in the chamber.

Abstract: An apparatus employing pressure transients for transporting fluids from a first reservoir to a second reservoir, includes at least one partly enclosed space and a body. The body is movable relative to the interior of the space. The apparatus also includes at least one first conduit and at least one second conduit in fluid communication with the opening via a third conduit, and connected to the first and second reservoir, respectively. An opening in the enclosed space allows a fluid to flow alternately in the direction into and out of the space and which opening is connected to a third conduit. At least one solid object is arranged to fall onto and collide with the body so as to generate pressure transients in the space to produce a flow of fluid in the direction from the space towards the second reservoir, and to produce a flow of fluid in the direction from the first reservoir towards the space.

Abstract: Methods to induce pressure transients in fluids for use in hydrocarbon recovery operations. Pressure transients are induced in a fluid by a collision process. The collision process employs a moving object that collides outside the fluid with a body that is in contact with the fluid inside a partly enclosed space. The pressure transients must be allowed to propagate in the fluid. The fluid may be one or more of the following group: primarily water, consolidation fluid, treatment fluid, cleaning fluid, drilling fluid, fracturing fluid and cement.

Abstract: A method for the recovery of hydrocarbon from a reservoir includes arranging a chamber in fluid communication with the reservoir via at least one conduit. The chamber includes first and second wall parts movable relative to each other. An impact pressure is provided in the fluid to propagate to the reservoir via the conduit, where the impact pressure is generated by a collision process between an object arranged outside of the fluid and the first wall parts for the first wall part to impact on the fluid in the chamber. The chamber is arranged to avoid a build-up of gas-inclusions where the first wall part impacts on the fluid. This may be obtained by arranging the conduit in or adjacent to the zone where the gas-inclusions naturally gather by influence of the gravitational forces, or by placing the first wall part impacting on the fluid away from this zone.

Abstract: A method to induce pressure transients in fluids for use in hydrocarbon recovery operations by inducing the pressure transients in a fluid by a collision process. The collision process employs a moving object (103,203,303,403) that collides outside the fluid with a body (102,202,302,402) that is in contact with the fluid inside a partly enclosed space (101,201,301,401). Furthermore, the pressure transients must be allowed to propagate in the fluid. The fluid may be one or more of the following group: primarily water, consolidation fluid, treatment fluid, cleaning fluid, drilling fluid, fracturing fluid and cement.

Abstract: An apparatus employing pressure transients for transporting fluids from one reservoir to another, includes an at least partly enclosed space, and a body herein, where the body is movable relatively to the interior of the space. The apparatus further includes an opening in the enclosed space to allow a fluid to flow alternately in the direction into and out, and conduits in fluid communication with the opening and connected to the reservoirs. Further, an object is arranged to collide with the body so as to generate pressure transients in the partly enclosed space in order to produce a flow of fluid in the direction from the partly enclosed space towards the second reservoir, and to produce a flow of fluid in the direction from the first reservoir towards the partly enclosed space.

Abstract: The invention relates to methods to induce pressure transients in fluids for use in hydrocarbon recovery operations. The invention is further characterized by inducing the pressure transients in a fluid by a collision process. The collision process employs a moving object (103, 203, 303, 403) that collides outside the fluid with a body (102, 202, 302, 402) that is in contact with the fluid inside a partly enclosed space (101, 201, 301, 401). Furthermore, the pressure transients must be allowed to propagate in the fluid. The fluid may be one or more of the following group: primarily water, consolidation fluid, treatment fluid, cleaning fluid, drilling fluid, fracturing fluid and cement.