Wake reduction structure for enhancing cavity flow in generator rotor endwindings

A gas cooled dynamoelectric machine, comprising:

• a rotor having a spindle and a body portion;
• a rotor winding comprising axially extending coils disposed on said body portion and spaced, concentric endwindings extending axially beyond at least one end of said body portion, said endwindings and said spindle defining an annular space therebetween;
• a plurality of spaceblocks located between adjacent ones of said endwindings thereby to define a plurality of cavities, each bounded by adjacent spaceblocks and adjacent endwindings and open to said annular space;
• and
• each said spaceblock having first and second sidewall portions engaging said adjacent endwindings, an upstream wall, and a downstream wall, said downstream wall of at least one of said spaceblocks having convexly curved, aerodynamic contour for reducing the extent and strength of the generated wake.