The Bladeless Propeller 



'y. 



THEORY ( REF. 8) 



EXPERIMENTS : 

 O RPI, 0,, ' 35 

 D RPI, j8|i = 45 



IDEAL 

 AUGMENTER 



Fig. 9 - Static performance of an axial-flow 

 bladeless propeller 



IDEAL 

 AUGMENTER 



Fig. 10 - Static performance of an axial-flow 

 bladeless propeller 



and the calculated thrust augmentation ratio is lower than that predicted by the 

 two-dimensional theory. Furthermore, the strip theory predicts for each area 

 ratio an optimum spin angle. The discrepancy between the two theories in- 

 creases as the density ratio increases. A comparison of the results of the two 

 theories for a density ratio of 1.0 is presented in Fig. 11. It should be noted 

 that neither of the two theories accounts for the adverse effect of mixing during 

 the deflection phase. Although in remarkably good agreement with experimental 



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