Abstract: A downhole retrieval tool for engaging and retrieving an object from a wellbore includes a mandrel and a grapple having a contracted position and an expanded position. In the expanded position, the grapple engages the object for retrieval. The grapple is operably associated with an expansion member disposed on the mandrel to facilitate movement of the grapple between the contracted and expanded positions. The expansion member is releasably connected to the mandrel. In the event that the downhole tool and object, once secured to each other, are unable to be retrieved from the wellbore, the expansion member can be released from the mandrel which, in turn, causes the grapple to release from the object so that the downhole tool can be removed from the wellbore. A stored energy member facilitates movement of the grapple from the contracted position to the expanded position.

Abstract: A hydraulic connector for a wellhead hub is provided that includes a piston and a bottom portion configured to move in an axial direction via hydraulic pressure applied to one or more hydraulic ports in the connector. The movement of the piston and the bottom portion moves a ring and a segment of the connector in a radial direction to engage recesses in the wellhead hub. The connector may be unlocked by applying hydraulic pressure to a hydraulic port of the connector. A system and method of operating the connector are also provided.

Abstract: A pressure tolerant battery that may be utilized in a subsea riser includes one or more lithium polymer cells enclosed in a pressure compensated housing. The pressure tolerant battery can be mounted on a landing string a disposed in the riser annulus to provide electrical power to landing string and subsea well system devices.

Abstract: A drilling apparatus (1) provides continuous rotation, and in some embodiments also vertical translation of the drill bit, such that weight can be kept on the bit and drilling can continue uninterrupted during connections. The connection is made in a pressure chamber formed by seals (2, 4) and spacers (15, 16). An upper snubber (5) grips the drill string above the joint and a lower snubber (6) grips it below the joint. The top drive is decoupled as the snubbers take over drill string drive, and apply a differential torque so that the connection is made. This achieves continuous rotation during the connection, and by use of an extension sub (18) drilling is also continuous.

Abstract: A seal includes an elastomeric material and a plurality of nanosprings filling the elastomeric material to form a filled elastomeric composite that provides the seal. A spring constant of the nanosprings is within a selected range of an effective spring constant of the elastomeric material such that a durometer of the filled elastomeric composite at an elevated temperature is greater than the durometer of the elastomeric material alone at the elevated temperature. The seal may be used to seal a first component to a second component where both components are configured to perform a task below the surface of the earth.

Abstract: A packer has a swellable element and has end rings and compressible elements at each end of the swellable element. The packer may be first set using internal bore pressure to compress one of the compressible elements against one of the end rings with a first hydraulic setting mechanism. The packer may then be set a second time using annulus pressure to compress against the other compressible element with a second hydraulic setting mechanism. Either way, the compressible elements are compressed to expand out to the borehole and to limit extrusion of the swellable element outside the compressed elements.

Abstract: A valve system for ensuring well closure upon exposure to a predetermined condition even where a well access line is disposed through the valve. This system may be configured with a supplemental power supply capable of effectuating a cutting closure of the valve. Thus, any obstructing well access line such as coiled tubing may be cut during closure to ensure sealing off of the well, even if the cutting mechanism is separated from its traditional power supply by shear or parting of a portion of the landing string. Once more, the supplemental power sufficient for a cutting closure is only provided in the event of a predetermined condition such as the emergence of a potentially hazardous tubular separation.

Abstract: An isolation method is described for gravel packed zones separated by at least one packer and having an auxiliary conduit passing through the packer into adjacent zones. The conduit includes at least one each of a shunt tube, flow housing, annular space, and isolation valve housing. The flow housing, the annular space, and the isolation valve housing are all annular and formed between two concentric pipes. The method includes running in an assembly of screens isolated by at least one packer with at least one auxiliary conduit extending into adjacent zones defined by the packer when the packer is subsequently set. The method also includes closing flow in said conduit to prevent flow into shunt tubes during production based on creating a flow barrier in the annular space, the flow housing, or the isolation valve housing, the shunt tubes supplying slurry through the auxiliary conduit prior to the production.

Abstract: A flow restriction device for controlling flow of a fluid into a wellbore tubular from a production zone. The device comprises a housing and at least one divergent passageway having a throat section and a divergent section disposed within the housing, wherein the average angle of divergence in the divergent section is between 2° and 40°. Fluid is directed from the production zone, through the divergent passageway and into the wellbore. The divergent passageway may or may not comprise a convergent section before the throat. Also described is a flow restriction device in which the discharged flow is aligned at an angle of between 0 and 60 degrees of the direction of flow within the wellbore tubular. The flow restriction device is used to control distributed fluid flow into a wellbore tubular.

Abstract: The present invention provides a method for producing hydrocarbon gas from a wellbore and a control valve assembly for said wellbore. The wellbore comprises a wellhead, a production zone, a production tubing, and a velocity string installed inside the production tubing. The method comprises allowing gas to flow from the production zone through the velocity string, said gas forming a primary gas stream, and controlling the flow of gas from the annulus between the outer wall of the velocity string and the inner wall of the production tubing to the primary gas stream by means of the control valve wherein a controlled mass flow of said gas is combined with the primary gas stream.

Abstract: A disclosed reverse-out valve includes an upper mandrel, a lower mandrel movable with respect to the upper mandrel, and a reverse activated plug device arranged on the upper mandrel and including a piston arranged within a piston chamber of the upper mandrel and a prop extending longitudinally from the piston, wherein the piston chamber includes a first end and a second end, the reverse activated plug device further including a closure device movable between an open position where the piston is arranged at the first end and the prop holds the closure device open such that a reverse-circulation fluid is able to bypass the reverse activated plug device, and a closed position, where the piston is arranged at the second end and the prop is moved to allow the closure device to close and thereby prevent the reverse-circulation fluid from bypassing the reverse activated plug device.

Abstract: An sleeve valve for a well assembly includes at least one set of passages extending through a tubular body between the central passage and an exterior of the tubular body and a sleeve slidably located within the central passage of the valve body adapted to selectably sealably cover or uncover the at least one sets of passages. A shifting tool for actuating the sleeve valve is connectable to a tool string and includes a shifting bore with an actuating piston extending from a central bore through the shifting tool and first and second key bores extending radially inwards from the outer surface each having a piston keys located therein. Each of the first and second piston keys is operably connected to the actuating piston so as to be extended from the outer surface when the central bore is supplied with a pressurized fluid.

Abstract: A downhole tool has a housing, mandrel, and ball seat. The housing defines a first bore, and the mandrel defines a second bore. The mandrel is disposed in the first bore of the housing and defines an annular space with the housing. The ball seat is rotatably disposed in the second bore of the mandrel and defines an interior passage with a seat profile. First and second pistons are disposed in the annular space on opposing sides of the ball seat. These first and second pistons are movable along an axis of the tool in the annular space in opposing directions and are adapted to rotate the ball seat. Additionally, first and second biasing members are disposed in the annular space and bias the first and second pistons toward one another to reset the ball seat in the absence of pressure.

Abstract: A down-hole tool for pressure testing production tubing within a borehole of a well returning the well to production, includes an anti-rotational device comprising a tubular housing having a first end, a second end, an outer surface, and at least one anti-rotational wing disposed on the outer surface of the tubular housing, radially extendable to engage a radial surface of the borehole to anchor the production tubing thereto; a valve for controlling the flow of down-hole fluids within the production tubing, the valve comprising a first valve member fixedly positioned within the tubular housing of the anti-rotational device and a second valve member positionable between a closed position and an open position; and a reactivation device comprising means for axially engaging an axial surface of the borehole, the reactivation device affixed to the first end of the tubular housing, wherein the production tubing may be pressure tested when the valve is in the closed position.

Abstract: A safety system for a well having a cable deployed electronic submersible pump includes a barrier valve having a control line for opening and closing the valve, a first flapper safety valve assembly, and a second flapper safety valve assembly. The second flapper safety valve allows the cable for the pump to pass through the second flapper safety valve when the valve is in a closed position. An integral flapper safety valve assembly incorporates the first and second flapper safety valves.

Abstract: An interlock device for connection within a load path of a tubular support device to lock the tubular support device in a closed position in response to detecting a load suspended from the tubular support device. The interlock device includes a first member moveably connected to a second member and a biasing mechanism operationally connected to the first member and the second member providing a load setting resisting movement of the first member and the second member relative to one another. The first and the second member may be rotationally locked with one another to transmit rotation across the interlock device to the elevator.

Abstract: A well system includes a deflector arranged within a main bore of a wellbore and defining a first channel that exhibits a predetermined diameter and communicates with a lower portion of the main bore, and a second channel that communicates with a lateral bore. A bullnose assembly has a bullnose tip, a piston movably arranged within the bullnose tip, and a wedge member operatively coupled to the piston such that movement of the piston correspondingly moves the wedge member. A coil is arranged about the bullnose tip and in contact with the wedge member, and the piston is actuatable to move the wedge member and thereby radially expand the coil. When the coil is radially expanded, the diameter of the bullnose tip exceeds the predetermined diameter.

Abstract: A downhole power generation system includes a tubular power generation device configured to be disposed in an annular space around a portion of a production tubing, wherein the power generation device is switchable between a power generation mode and a bypass mode. The system also includes a power storage device electrically coupled to the tubular power generation device and configured to store power generated by the power generation device. The power generation device comprises at least one power generation path and at least one bypass path. The at least one power generation path comprises at least one power generation mechanism which generates power when traversed by fluid. The at least one power generation path is open in the power generation mode and closed in the bypass mode.

Abstract: A downhole power generation device includes a tubular housing configured to be disposed within an annular space and around a portion of production tubing. The housing includes a flow compartment configured to receive a flow of fluid therethrough when the power generation device is in a power generation mode, and an electronics compartment comprising a controller and a power generation unit. The downhole power generation device further includes a turbomachinery system comprising a rotor disposed within the flow compartment and comprising a rotor hub and a plurality of rotor blades, wherein the rotor rotates when the flow of fluid traverses the flow compartment. The downhole power generation device also includes a port coupled to the flow compartment, through which fluid enters the flow compartment.

Abstract: A downhole tool includes an outer tubular member and an inner tubular member. The outer tubular member may have one or more screens coupled thereto, a packer coupled thereto, and a shunt tube isolation valve coupled thereto. A first sleeve may be coupled to the packer and move from a first position to a second position. The packer may actuate into a set state when the first sleeve is moved to the second position, and the packer may isolate first and second portions of an annulus from one another when in the set state. A shunt tube may be coupled to the packer and provide a path of fluid communication from the first portion of the annulus, through the packer, and to the second portion of the annulus when the packer is in the set state.

Abstract: A method for completing a wellbore in a subsurface formation includes providing a sand screen assembly representing one or more joints of sand screen, joint assembly, and packer assembly. The packer assembly has at least one mechanically-set packer with at least one alternate flow channel. The sand screen assembly and joint assembly also each have transport conduits for carrying gravel slurry, and packing conduits for delivering gravel slurry. The method also includes running the sand screen assembly, connected joint assembly and packer assembly into the wellbore, and setting a sealing element of the packer assembly into engagement with the surrounding wellbore. Thereafter, the method includes injecting gravel slurry into the wellbore to form a gravel pack such that a reserve of gravel packing material is placed above the sand screen assembly. A wellbore completion apparatus is also provided that allows for placement of the gravel reserve.

Abstract: A completion joint 100 has two sand control jackets 120A-B connected on each end of an intermediately-mounted inflow control device 130. Both jackets 120A-B communicate with a housing chamber 155 through dedicated open end-rings 140A-B. The basepipe's flow openings 118 are isolated from this housing chamber 155 by a sleeve 160 fitted with flow ports 170. The housing 150 is removable to allow access to the flow ports 170 for pinning to configure the ports 170 open or closed for a given implementation.

Abstract: A well pump assembly includes rotary pump and a submersible motor. A shroud surrounds the pump intake and the motor. The shroud has an open upper end in fluid communication with the pump intake for drawing well fluid along an upper flow path down the shroud into the pump intake. A dip tube is secured to and extends downward from a junction with a lower end of the shroud. The dip tube is in fluid communication with the pump intake and has an open lower end for drawing well fluid along a lower flow path up the dip tube to the pump intake. The upper flow path has a minimum flow area that is smaller than a minimum flow area of the lower flow path. The dip tube has a smaller outer diameter than an outer diameter of the shroud.

Abstract: An electric submersible pump (ESP) inverted shroud assembly is described. An ESP assembly includes an inverted shroud separating an ESP pump from a well casing, the ESP pump rotatably coupled to an ESP motor, the inverted shroud having an opening on an upstream terminal side, at least a portion of the ESP motor extending through the opening, the portion of the ESP motor extending through the opening exposed to working fluid, and the opening sealed to the working fluid. An ESP assembly includes an inverted shroud, and an ESP motor including a head, housing and base, the head of the ESP motor at least partially inside the inverted shroud, and the housing and base of the ESP motor at least partially outside the inverted shroud.

Abstract: A method is provided for treating at least a portion of a subterranean formation. The method includes introducing a treatment fluid including a composite particle, which includes proppant incorporated into or attached to a swellable material and/or swellable materials, into a subterranean formation via a wellbore; and increasing the buoyancy of the composite particle including proppant by either mixing it with a treatment fluid or mixing it with a treatment fluid and triggering the swellable material and/or swellable materials to swell.

Abstract: Batch initiation and/or exploitation phases of in situ solution mining of a mineral from an underground evaporite mineral stratum. The initiation phase may comprise a lifting step which employs a lithological displacement (lifting) of this stratum from an underlying non-evaporite stratum with application at the strata interface of a lifting hydraulic pressure greater than overburden pressure by a solvent suitable to dissolve the mineral; a soaking step for dissolution of mineral upon contact with stationary solvent, and a brine extraction step. The method may further comprise one or more exploitation phases carried out after the initiation phase. The exploitation phase may comprise a partial filing or filling step with the same solvent or different solvent than during lifting, another soaking step, and another brine extraction step. The lifting, cavity partial filing/filling, and brine extraction steps are being discontinuous. The evaporite mineral stratum preferably comprises trona.

Abstract: Alpha-hydroxy alkyl esters have been found to perform as hydrogen sulfide scavengers. A method of scavenging hydrogen sulfide includes contacting a fluid containing hydrogen sulfide with a treatment fluid including an alpha-hydroxy alkyl ester. Accordingly, the alpha-hydroxy alkyl ester reacts with the hydrogen sulfide to reduce the amount of hydrogen sulfide in the fluid. A broad range of alpha-hydroxy alkyl esters are disclosed.

Abstract: A method for removal of a compound from a crude hydrocarbon gas stream to be obtained from a sub-sea well is disclosed. The method comprises bringing the crude hydrocarbon gas stream in contact with a treatment solution comprising an absorbent at least partly selective to the compound to be removed, thereby obtaining a rich treatment solution and a compound depleted gas stream, regenerating the treatment solution comprising the absorbent by desorbing the compound from the rich treatment solution, thereby obtaining a compound stream.

Abstract: A method and system for steering a rotary steerable tool in a borehole. A method includes determining an azimuthal angle between a reference direction and a reference point on a direction determination component of a tool string. The direction control component is remote from the rotary steerable tool. The azimuthal angle and a time at which the angle was determined are communicated to a rotary steerable tool direction control system. A steerable shaft of the rotary steerable tool is deflected based on the azimuthal angle and the time at which the angle was determined, thereby directing the rotary steerable tool in a predetermined direction.

Abstract: A method can include providing a pump connected to a power cable with a smooth surface; providing a stuffing box with a valve configured to form a seal with the smooth surface of the power cable in a closed state and to form a passage for the pump as connected to the power cable in an open state; providing a lubricator; providing a blow-out protector with a valve configured to form a seal with the smooth surface of the power cable in a closed state and to form a passage for the pump as connected to the power cable in an open state; and controlling the states of the valves while lowering the pump via the power cable through the stuffing box, the lubricator, and the blow-out protector to position the pump into a bore of a well. Various other apparatuses, systems, methods, etc., are also disclosed.

Abstract: Borehole data presentation systems and methods that facilitate communication of volumetric logging data to a surface processing system for presentation to a driller or other user interested in visualizing the formations surrounding a borehole. The disclosed systems optionally tailor the telemetry stream to match the chosen display technique, thereby maximizing the logging system utility for the driller. Variable opacity of certain data regions or certain data discontinuities greatly facilitates data comprehension, particularly when true three-dimensional display technologies are employed. Holographic or stereoscopic display technologies may be employed to show the three-dimensional dependence of measured formation properties such as resistivity, density, and porosity. Alternatively, the radial axis can be used to represent a formation parameter value, thereby enabling cylindrical cross-plots of multiple measurements.

Abstract: Systems and methods for determining stresses in pipe under non-uniform exterior loads to test the pipe design for structural integrity by approximating non-uniform exterior loads on the pipe and performing a stress analysis of the pipe under the non-uniform exterior loading to determine the stresses in the pipe.

Abstract: A method for a rapid verification of satisfactory clean-up at the end of the completion process when starting production of petroleum fluids while the completion rig is still at the well. The method includes marking one or more of separated zones along the well by one or more distinct tracers, before starting production. The tracers are added along with the completion or the clean-up fluid, and the tracers are arranged to be released by relative high concentrations from each zone to an inflowing fluid of oil or gas.

Abstract: A measurement-while-drilling servo-actuator for use in mud-pulse telemetry, which determines linear position of a poppet valve therein without counting revolutions of a stepper motor which positions said poppet valve. A sensor senses a magnetic field intensity value, or an inductance value, which is proportional to the position of the poppet valve relative to the sensor. A look-up table of reference outputs corresponding to known position of the poppet valve is used to determine the position of the poppet valve. A method of determining a position of a poppet valve in a mud pulser is further disclosed.

Abstract: The present invention relates to a downhole tool (10) to be submerged into a well fluid from a top of a well, comprising a first tool section (21), a tool housing (3) having an inner face (4), a downhole communication module (1) for communicating through a well fluid in a downhole well to operate the downhole tool, comprising a piezoelectric transceiver (5) having a first face (6) and a second face (7) and being arranged in the tool housing, wherein an element (8) is arranged between the piezoelectric transceiver and the tool housing, and the element is arranged in abutment with the first face of the piezoelectric transceiver and the inner face of the housing, so that the tool housing acts as a transducer when the piezoelectric transceiver is activated and enlarges in a radial direction of the tool housing, forcing the tool housing outwards and sending a signal through the well fluid. The present invention also relates to a downhole system and a communication method.

Abstract: An assembly can include a casing string with an outer surface. The assembly can also include an antenna for wirelessly communicating data by generating a surface wave that propagates along an interface surface. The antenna can be positioned coaxially around the casing string. The antenna can include a cylindrically shaped conductor that is positionable coaxially around an outer surface of a casing string for generating a magnetic field component of the surface wave that is non-transverse to a direction of propagation of the surface wave along the interface surface. The antenna can also include a pair of conductive plates positioned at an angle to the cylindrically shaped conductor for generating an electric field component of the surface wave.

Abstract: A method for signal communication between a well drilling instrument and the Earth's surface includes generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field includes encoded measurements from at least one sensor associated with the instrument. A signal corresponding to an amplitude of the electromagnetic field is measured and the measurements from the measured signal are decoded. The signal comprises a voltage measured across electrodes or a voltage induced in an electromagnetic receiver disposed at a selected depth below the Earth's surface. The selected depth is at least the depth of a formation below the water table having a highest resistivity within 500 meters of the surface.

Abstract: A communications path between a surface control system and downhole equipment includes a network of wirelessly interconnected communication devices that are located along a conduit. When the communications path fails or cannot be established during performance of a downhole operation, a mobile master communication tool that is in communication with the surface system can be deployed within the wireless range of one of the devices to provide an alternative communication path between the surface system and the downhole equipment. In other embodiments, the alternative communication path can be a temporary path to provide for communications before the network is fully deployed.

Abstract: One embodiment includes a method comprising receiving an acoustic signal that is propagated along a drill string. The method also includes correlating the acoustic signal to a first stored acoustic signal representing a first symbol, wherein the first stored acoustic signal is acquired from a propagation along the drill string in an approximately noise free environment.

Abstract: A method for controlling well bore pressure based on model prediction control theory and systems theory, includes: detecting a well bottom pressure, a stand pipe pressure, a casing pressure, an injection flow rate and an outlet flow rate during the drilling operation process and determining the presence of overflow or leakage; if there is no overflow or leakage, then fine-adjusting the wellhead casing pressure according to the slight fluctuations of the well bottom pressure, the stand pipe pressure or the casing pressure; if there is overflow or leakage, simulating and calculating the overflow or leakage position and starting time of the overflow or leakage, predicting the variation over a future time period of the well bore pressure in the well drilling process, and utilizing an optimization algorithm to calculate the control parameter under a minimum of an actual well bottom pressure difference during the future period.

Abstract: Implementations of computer-implemented methods, computer-readable media, and computer systems for interactive wellbore design management include displaying a well design including a wellbore profile representing a wellbore in a user interface. A first well component object is positioned at a first user interface position in the user interface. The first user interface position corresponds to a first well position of a first well component represented by the first well component object in the wellbore. A positioning of a second well component object at a second user interface position in the user interface is detected. The second user interface position corresponds to a second well position of a second well component represented by the second well component object in the wellbore. Using the well design, a compatibility of the second well component positioned at the second well position with the first well position of the first well component is determined.

Abstract: Mud pulse telemetry. The various embodiments are directed to methods and systems of encoding data in a mud pulse telemetry system, where at least a portion of the data is encoded the time between pressure transitions. Moreover, the various embodiments are directed to detection methods and systems that detect the pressure transitions at the surface.

Abstract: A system for pressure testing a formation includes a downhole tool configured to measure formation pressure, storage containing pressure parameters of a plurality of simulated formation pressure tests, and a formation pressure test controller coupled to the downhole tool and the storage. For each of a plurality of sequential pressure testing stages of a formation pressure test, the formation pressure test controller 1) retrieves formation pressure measurements from the downhole tool; 2) identifies one of the plurality of simulated formation pressure tests comprising pressure parameters closest to corresponding formation pressure values derived from the formation pressure measurements; and 3) determines a flow rate to apply by the downhole tool in a next stage of the test based on the identified one of the plurality of simulated formation pressure tests.

Abstract: The invention is a rotary engine comprised of at least one and usually a plurality of independent partial engines. Two different processes can be carried out in each independent partial engine both of which are used to operate the engines. The processes of the invention are basically two different and separate closed cycle processes that can both operate within the same geometric confinement, i.e. the same expansion chamber or expansion chambers, at the same time. The primary process performs the main function of converting heat to kinetic energy and is necessary in all engines of the invention. It is a unique process that uses the expansion of gases and also the contraction of the condensing gases after their expansion. The secondary process is needed for start-up and to provide additional power in case the engine might go into a stall. In most engines of the invention both processes are needed to operate the engine.

Abstract: A compression mechanism can include a first scroll member, a second scroll member, and an Oldham coupling. The first scroll member can include a base plate. The second scroll member can meshingly engaged with the first scroll member, and include a first radially extending slot. The Oldham coupling can include a ring portion disposed about the base plate and a first radially extending key portion disposed in the first radially extending slot. The ring portion and the key portion can include a pair of upper surfaces and a pair of lower surfaces. At least one pair of upper surfaces or lower surfaces can be substantially coplanar.

Abstract: A method of balancing a gas turbine engine rotor, including axisymmetrically removing an annular portion of the balancing flange exceeding that required to provide the unbalance correction, and creating the unbalance correction by non-axisymmetrically removing material from the balancing flange. In one embodiment, the configuration of a theoretical notch in the balancing flange that would create the unbalance correction is determined. The unbalance correction is created by removing material from the balancing flange to create a protuberance protruding radially from a remainder of the balancing flange, the protuberance having a height corresponding to the depth of the theoretical notch, a circumferential width corresponding to the arc angle of the theoretical notch, and a circumferential position diametrically opposed to the circumferential position of the theoretical notch. A gas turbine engine rotor is also discussed.

Abstract: A method of establishing a boundary for a material improvement process on a workpiece is disclosed. The method may include identifying a maximum allowable damage depth on the workpiece; identifying a maximum constant thickness line on the workpiece at an extent of the maximum allowable damage depth; identifying a peak vibratory stress gradient on the workpiece; identifying a peak combined engine stress on the workpiece; and specifying the boundary for the material improvement process on the workpiece relative to the maximum constant thickness line, peak vibratory stress gradient, and peak combined engine stress.

Abstract: A VTG cartridge (1, 2) of an exhaust-gas turbocharger (2), with a blade bearing ring (3), and a disk (4), which is spaced apart from the blade bearing ring (3) and together with the latter delimits a hot-gas passage (5). The disk (4) is constructed from at least two layers (6, 7, 6?, 7?), which bear loosely against one another in the assembled state of the disk (4).

Abstract: The present invention relates to a blade of a row of rotor blades or stator blades for use in a turbomachine, with the blade being designed with a substantially convex suction side and a substantially concave pressure side as well as with a leading edge, onto which the flow passes, and a trailing edge, away from which the flow passes. The blade has at least one contour recess provided on at least one of the blade sides including the suction side and the pressure side, wherein the contour recess includes a step edge, a contour corner and a flank face provided between the step edge and the contour corner. The contour recess extends over at least a part of the profile depth and/or the profile height of the blade.

Abstract: Various embodiments of the invention include turbine buckets and systems employing such buckets. Various particular embodiments include a turbine bucket having: an airfoil having: a suction side; a pressure side opposing the suction side; a leading edge spanning between the pressure side and the suction side; and a trailing edge opposing the leading edge and spanning between the pressure side and the suction side; and a base connected with a first end of the airfoil along the suction side, pressure side, trailing edge and the leading edge, the base including a non-axisymmetric contour proximate a junction between the base and the airfoil.