| 摘要 |
A stator blade for a gas turbine with sequential combustion, has a blade airfoil which extends in the radial direction between a blade tip and a shroud, with cooling passages extending inside the blade airfoil, through which a cooling medium can flow for cooling the blade and can then discharge from the stator blade into the hot gas flow flowing through the turbine. The blade airfoil has a sharply curved shape in space in the radial direction, and three cooling passages, which extend in the radial direction, arranged inside the blade airfoil in series in the hot gas flow direction and are interconnected by deflection regions, which are arranged at ends of the blade airfoil, so that the cooling medium flows through the cooling passages one after the other, with change of direction. The cooling passages follow the curvature of the blade airfoil in space in the radial direction. |
| 主权项 |
1. A stator blade for a gas turbine, the stator blade having a blade airfoil extending in a radial direction between a blade tip and a shroud, with cooling passages extending inside the blade airfoil, through which a cooling medium flows for cooling the stator blade and then discharges from the stator blade into a hot gas flow which flows through the turbine, the blade airfoil having a sharply curved shape in space in the radial direction, a plurality of cooling passages, which extend in the radial direction, are arranged inside the blade airfoil, in series, in the hot gas flow direction and deflection regions, which are arranged at ends of the blade airfoil, are interconnected so that the cooling medium flows through the cooling passages one after the other, with change of direction, the cooling passages follow a curvature of the blade airfoil in space in the radial direction, wherein an entry of a first cooling passage, via a cooling air inlet which extends through a shroud, is in communication with an outer space which lies above the shroud, and the first cooling passage is connected to a start of a second cooling passage by a first deflection region, and a cross-sectional area at an entry of the second cooling passage is larger than a cross-sectional area at an outlet of the first cooling passage, and a throttling element, for throttling a mass flow of cooling medium which flows through the cooling air inlet, is arranged in a region of the cooling air inlet, the throttling element having the form of a plate which is provided with at least one opening, the throttling element closes off the entry of the cooling air inlet and is soldered into the shroud, wherein a ratio of the cross-sectional area at the entry of the second cooling passage to the cross-sectional area at the outlet of the first cooling passage is about 1.6 and wherein an end of the second cooling passage is connected to a start of a third cooling passage by a second deflection region, a throttling device, for the controlled extraction of cooling medium for the cooling of an outer platform and of a part of a trailing edge, is provided in the second deflection region, a cross-sectional area at an entry of the third cooling passage is smaller than a cross-sectional area at an outlet of the second cooling passage and cross-sectional areas of the three cooling passages halfway up the stator blade are in a ratio of 1:2:1. |
