Abstract: Leakage of a working fluid from a shaft sealing device of a turbomachine which handles a liquid as the working liquid is reduced and also unstable fluid force which acts on a rotor is reduced. For this purpose, the turbomachine has a rotor having an impeller, a bearing which rotatably supports the rotor, a casing which contains the rotor therein and forms a stationary flow passage, and the shaft sealing device which reduces the leakage of the working fluid through a gap part between the casing and the rotor. The working fluid is a liquid. A plurality of axial grooves which are intermittently arranged in axial direction and circumferential direction of the rotor with a land part being interposed are provided in an inner circumferential surface of the shaft sealing device.

Abstract: A rotating electrical machine includes a rotating electrical machine body including a stator, a rotor, a fan configured to circulate a coolant for cooling the stator and the rotor, and a casing containing the stator, the rotor and the fan; and a cooler connected to the rotating electrical machine body. The coolant flows from the machine body into the cooler. The cooler cools the coolant. The coolant flows out of the cooler into the machine body. The cooler has a flow resistance Ra satisfying a relation 0.15<(Ra/Rm)<(P0/P1), wherein Ra is a flow resistance of the coolant in the cooler, Rm is a flow resistance of the coolant in the rotating electrical machine body, P0 is a shutoff pressure of the fan, and P1 is a pressure at an operating point of the fan when the flow resistance Ra of the cooler is assumed to be zero.

Abstract: A method for manufacturing a neutral ring includes connecting a cut-off neutral ring to an arc-shaped connection element. The method also includes filling an insulator between the cut-off neutral ring and a connection element. The neutral ring shunts the rotor coil in three phases.