Foa 



noncondensing primary, are presented in Figs. 15 and 16. The thrust augmentation 

 ratios predicted by the Sarro-Kosson strip theory for very low spin angles and 

 disc loadings are considerably higher than those predicted for the same conditions 

 by the two-dimensional theory. This is primarily due to the fact that the analyti- 

 cal model considered in the latter theory makes no provision for the recovery of 

 the transverse momentum of the two flows after the deflection phase. Work on 

 the theory of thebladeless propeller with a condensing primary is in progress at 

 R.P.I, and at Grumman, but no numerical result is yet available at this writing. 



6.0 



5.0 



4.0 



3.0 



2.0 



1.0 



10 



19 20 



25 



30 



Fig. 15 - Comparison of the Sarro-Kosson 

 strip theory with the results of the Grum- 

 man steam-water tests, for a noncondensing 

 primary (Refs. 14 and 15) 



1366 



