Abstract: A reverse flow, gas cooled dynamoelectric machine includes a rotor mounted fan at each machine end for circulating gas coolant throughout the machine. Improved pressure and efficiency for the fan is achieved by positioning stationary guide vanes upstream from the fan for directing gas coolant into the fan blades at an optimum angle. The invention is directed toward an improved guide vane assembly construction and composition.

Abstract: An integral nozzle-shield assembly for a gas-cooled dynamoelectric machine such as a large turbine-driven generator is described. The nozzle-shield assembly is formed of a non-conductive, non-magnetic material such as molded fiberglass and resin and serves to channel hydrogen gas between a heat exchanger and a rotor-mounted fan used to pump the gas through coolant passages in the dynamoelectric machine, and the assembly also provides a labyrinth seal over the fan blade tips. In one embodiment, the nozzle-shield assembly includes two 180-degree halves whose thickness varies circumferentially and which may be installed in a generator by bolting their outer edges to a stator frame member of the generator and bolting the halves together at the two radial joints between halves using flat metal plate connectors.

Abstract: A reverse flow cooled dynamoelectric machine if provided with cooling gas passages extending through a fan ring and a portion of the rotor spindle to the end turns of the rotor winding in a direction substantially corresponding to the direction of flow of the cooling gas as modified by a tangential component imparted to the gas by the rotation of the fan ring. This direction is the vector sum of the longitudinal component of the velocity of the gas as it approaches the passages and the tangential component imparted by the rotation of the fan ring. The exit end of each passage is circumferentially displaced from the inlet end opposite to the direction of rotation. The centerlines of the gas passages lie in planes spaced around the axis of rotation of the rotor and parallel to this axis.

Abstract: A reverse flow cooled dynamoelectric machine if provided with cooling gas passages extending through a fan ring and a portion of the rotor spindle to the end turns of the rotor winding in a direction substantially corresponding to the direction of flow of the cooling gas as modified by a tangential component imparted to the gas by the rotation of the fan ring. This direction is the vector sum of the longitudinal component of the velocity of the gas as it approaches the passages and the tangential component imparted by the rotation of the fan ring. The exit end of each passage is circumferentially displaced from the inlet end opposite to the direction of rotation. The centerlines of the gas passages lie in planes spaced around the axis of rotation of the rotor and parallel to this axis.

Abstract: A reverse flow cooled dynamoelectric machine is provided with guide vanes and a guide vane mounting assembly comprising means for mounting and positioning the guide vanes, and means for directing the flow of cooling gas from the fan to the cooler. A fan nozzle ring is attached to the machine stator. An outer vane support ring is fixed to the fan nozzle ring and is provided with a circumferentially extending dovetail recess along its inner face. An inner vane support ring is spaced radially inwardly from the outer support ring and is also provided with a dovetail recess along its inner face. A plurality of guide vanes having inner and outer dovetail end portions mating with the dovetail recesses of the inner and outer support rings are held in place by the support rings. An annular rub strip is disposed adjacent to the outer support ring and is fixed to the fan nozzle ring. The rub strip includes a serrated inner face which, with the tips of the fan blades, produces a seal.