Abstract: The invention concerns a method for starting a hydroelectric turbine (10) in a pumping mode, said turbine being provided with a runner (6) mechanically coupled to a shaft line (8) and a variable speed electric motor connected to a grid, a distributor (4) comprising guide vanes to control a flow of water to said runner, the method comprising: a) a step of operating the variable speed motor at least partly at fixed speed, said guide vanes being only partially opened, and of defining or calculating: data of a plurality of hydraulic characteristics (C1, C2, Ci) of the turbine for an operation without cavitation; data of an operation range of the electric motor, giving the speed of the motor as a function of its power; b) then a step of operating the turbine in a power control mode.

Abstract: The invention concerns a method for starting a hydroelectric turbine (10) in a pumping mode, said turbine being provided with a runner (6) mechanically coupled to a shaft line (8) and a variable speed electric motor connected to a grid, a distributor (4) comprising guide vanes to control a flow of water to said runner, the method comprising: a) a step of operating the variable speed motor at least partly at fixed speed, said guide vanes being only partially opened, and of defining or calculating: data of a plurality of hydraulic characteristics (C1, C2, Ci) of the turbine for an operation without cavitation; data of an operation range of the electric motor, giving the speed of the motor as a function of its power; b) then a step of operating the turbine in a power control mode.

Abstract: The invention concerns a method for starting a hydroelectric turbine (10) in a pumping mode, said turbine being provided with a runner (6) mechanically coupled to a shaft line (8) and a variable speed electric motor connected to a grid, a distributor (4) comprising guide vanes to control a flow of water to said runner, the method comprising: a) a step of operating the variable speed motor at least partly at fixed speed, said guide vanes being only partially opened, and of defining or calculating: data of a plurality of hydraulic characteristics (C1, C2, Ci) of the turbine for an operation without cavitation; data of an operation range of the electric motor, giving the speed of the motor as a function of its power; b) then a step of operating the turbine in a power control mode.

Abstract: The invention concerns a method for starting a hydroelectric turbine (10) in a pumping mode, said turbine being provided with a runner (6) mechanically coupled to a shaft line (8) and a variable speed electric motor connected to a grid, a distributor (4) comprising guide vanes to control a flow of water to said runner, the method comprising: a) a step of operating the variable speed motor at least partly at fixed speed, said guide vanes being only partially opened, and of defining or calculating: data of a plurality of hydraulic characteristics (C1, C2, Ci) of the turbine for an operation without cavitation; data of an operation range of the electric motor, giving the speed of the motor as a function of its power; b) then a step of operating the turbine in a power control mode.

Abstract: A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

Abstract: A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

Abstract: A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

Abstract: The present invention is a fuel injection method for a compression-ignition internal-combustion engine running in single-fuel or multi-fuel mode. The method, in a single-fuel mode, injects liquid fuel (Fuel1) into lower zone (Z1) and/or upper zone (Z2) of the combustion chamber and, in a multi-fuel mode, provides in the chamber mixing of an oxidizer with another fuel (Fuel2) and injection of liquid fuel (Fuel1) into lower zone (Z1) or both zones (Z1, Z2) of the combustion chamber.

Abstract: The present invention relates to a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injection (14) projecting the fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2), a piston (16) sliding in the cylinder, a combustion chamber (34) limited on one side by upper face (44) of the piston comprising a projection (48) extending in the direction of the cylinder head and arranged in the center of a concave bowl (46) with at least two mixing zones (Z1, Z2), and piston cooler (76) housed in the material of the piston. According to the invention, the piston cooler comprises at least one circumferential gallery (78, 82) concentric to piston bowl (46) and arranged opposite at least one mixing zone (Z1, Z2).

Abstract: The present invention is a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder, a cylinder head carrying fuel injection, a piston sliding in the cylinder, a combustion chamber limited on one side by upper face of the piston comprising a projection extending in the direction of the cylinder head and in the center of a concave bowl (46) with at least two mixing zones. The fuel injection projects fuel in at least two fuel jet sheets with different sheet angles, with a lower sheet having a jet axis C1 for one zone and an upper sheet having a jet axis for the other zone. The injection feeds fuel into the combustion chamber with a different flow rate for each sheet for dedicated targeting in the mixing zones of the combustion chamber.

Abstract: The present invention is a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injection means (14), a piston (16) sliding in the cylinder, a combustion chamber (34) limited on one side by an upper face (44) of the piston comprising a projection (48) extending in the direction of the cylinder head and located in a center of a concave bowl (46). The engine comprises injection projecting fuel in at least two fuel jet sheets. One of the zones comprises a toroidal volume (64) having center B with a flat bottom (56) into which fuel jets (40) of the lower sheet are injected so that an axis C1 of the lower sheet jets is contained between center B and projection (48).

Abstract: The present invention relates to a fuel injection method for a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injectors (14), a piston (16) sliding in the cylinder, a combustion chamber (34) delimited on one side by an upper face (44) of the piston comprising a projection (48) extending in the direction of the cylinder head and located in the center of a concave bowl (46) with at least two mixing zones (Z1, Z2). The injectors project fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2). The injection into the combustion chamber with the fuel jets (40) by one sheet (36) is in a radial direction (C1) which forms a non-zero angle (b2) with the radial direction (C2) of fuel jets (42) of the other sheet (38). The oxidizer is admitted into the cylinder in a swirling motion with a swirl number less than or equal to 1.5.

Abstract: The present invention relates to a compression-ignition direct-injection internal-combustion engine with a compression ratio ranging between 13.5 and 16.5 including a combustion chamber limited on one side by upper face (44) of a piston (16) comprising a projection (48) arranged in the center of a concave bowl (46) with at least two mixing zones (Z1, Z2), a fuel injection comprising at least one injector (30) projecting fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2). The fuel injector comprises two rows of injection orifices (33a, 33b) arranged one above the other with the number of orifices of each row (Ninf, Nsup) is greater than or equal to ?4·Ns+14 and less than or equal to ?4·Ns+16 for the lower sheet or ?4·Ns+18 for the upper sheet. Ns is the swirl number of this engine with a swirl number less than 1.5.

Abstract: The present invention is a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injection means (14), a piston (16) sliding in this cylinder, a combustion chamber (34) having on one side an upper face (44) of the piston comprising a projection (48) extending in the direction of the cylinder head and located at the center of a concave bowl (46). The engine comprises an injector projecting fuel in at least two fuel jet sheets with sheet injection angles (A1, A2), a lower sheet (36) of jet axis C1 and an upper sheet (38) of jet axis C2, at least two mixing zones (Z1, Z2) of the combustion chamber. According to the invention, one of the zones comprises a toroidal volume (64) of center B into which fuel jets (40) of the lower jet are injected in such a way that axis C1 of the lower jet is contained between center B and projection (48).

Abstract: A hydraulic turbine includes a rotor with a runner, which is concentrically surrounded by a stator, whereby the runner comprises a plurality of runner blades arranged and distributed in a ring around a rotor axis, and each runner blade extends between a runner crown and a runner band; whereby the stator comprises a plurality of guide vanes arranged and distributed in a ring around the rotor axis, and each guide vane extends between an upper stator ring and a lower stator ring; and whereby a predetermined clearance is provided at least between the runner band and the lower stator ring. A substantial reduction of pressure pulsations in the vane-less gap between said runner blades of said runner is achieved by substantially increasing said predetermined clearance.

Abstract: The present invention is a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder, a cylinder head carrying fuel injection, a piston sliding in the cylinder, a combustion chamber limited on one side by upper face of the piston comprising a projection extending in the direction of the cylinder head and in the center of a concave bowl (46) with at least two mixing zones. The fuel injection projects fuel in at least two fuel jet sheets with different sheet angles, with a lower sheet having a jet axis C1 for one zone and an upper sheet having a jet axis for the other zone. The injection feeds fuel into the combustion chamber with a different flow rate for each sheet for dedicated targeting in the mixing zones of the combustion chamber.

Abstract: The present invention is a fuel injection method for a compression-ignition internal-combustion engine running in single-fuel or multi-fuel mode. The engine has at least a cylinder (10), a piston (16) sliding in the cylinder, a combustion chamber (34) comprising two mixing zones (Z1, Z2) which are defined on one side by upper face of the piston comprising a projection extending in the direction of the cylinder head and located in a center of a concave bowl (48), a cylinder head (12) carrying fuel injection (30) projects liquid fuel (Fuel1) in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2), and intake (24, 26, 28) for an oxidizer and burnt gas exhaust (18, 20, 22).

Abstract: The present invention relates to a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injection means (14) projecting the fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2), a piston (16) sliding in this cylinder, a combustion chamber (34) delimited on one side by upper face (44) of the piston comprising a teat (48) extending in the direction of the cylinder head and arranged in the centre of a concave bowl (46) with at least two mixing zones (Z1, Z2), and piston cooling means (76) housed in the material of the piston. According to the invention, the cooling means comprise at least one circumferential gallery (78, 82) concentric to piston bowl (46) and arranged opposite at least one mixing zone (Z1, Z2).

Abstract: The present invention relates to a fuel injection method for a compression-ignition direct-injection internal-combustion engine comprising at least a cylinder (10), a cylinder head (12) carrying fuel injection means (14), a piston (16) sliding in this cylinder, a combustion chamber (34) delimited on one side by upper face (44) of the piston comprising a teat (48) extending in the direction of the cylinder head and arranged in the centre of a concave bowl (46) with at least two mixing zones (Z1, Z2), said injection means projecting fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2), characterized in that it consists in injecting into the combustion chamber the fuel jets (40) of one (36) of the sheets in a radial direction (C1) forming a non-zero angle (b2) with the radial direction (C2) of fuel jets (42) of the other sheet and in admitting the oxidizer in a swirling motion with a swirl number less than or equal to 1.5.

Abstract: The present invention relates to a compression-ignition direct-injection internal-combustion engine with a compression ratio ranging between 13.5 and 16.5 including a combustion chamber limited on one side by upper face (44) of a piston (16) comprising a projection (48) arranged in the center of a concave bowl (46) with at least two mixing zones (Z1, Z2), a fuel injection comprising at least one injector (30) projecting fuel in at least two fuel jet sheets (36, 38) with different sheet angles (A1, A2). The fuel injector comprises two rows of injection orifices (33a, 33b) arranged one above the other with the number of orifices of each row (Ninf, Nsup) is greater than or equal to ?4.Ns+14 and less than or equal to ?4.Ns+16 for the lower sheet or ?4.Ns+18 for the upper sheet. Ns is the swirl number of this engine with a swirl number less than 1.5.