Full-scale ejector experiments are expensive and difficult to implemen
t at engine exhaust temperatures. For this reason the utility of using
similarity principles, in particular the Munk and Prim principle for
isentropic now, was explored. Static performance test data for a full-
scale thrust augmenting ejector were analyzed for primary flow tempera
tures up to 1560-degrees-R. At different primary temperatures, exit pr
essure contours were compared for similarity. A nondimensional flow pa
rameter is then used to eliminate primary nozzle temperature dependenc
e and verify similarity between the hot and cold flow experiments. Und
er the assumption that an appropriate similarity principle can be esta
blished, properly chosen performance parameters were found to be simil
ar for both hot flow and cold flow model tests.