An analysis of rotating flow in a rotor stator gap with axial through
flow is presented. The analysis considers changes in mass, angular mom
entum, and static pressure that occur both between and across regions
where cooling flow is injected, and may be applied to both smooth and
rough rotors and stators. A simple calculation shows that most turboge
nerator gap flows are undeveloped with sin average tangential velocity
different than half the rotor speed. The analysis is compared to data
from a recent set of experiments. Comparisons are made for gap flow w
ith both a constant and varying axial through flow; the latter caused
by air injection from the rotor. In both cases, the agreement is extre
mely good.