Gas-Turbine Powerplants For Two-Phase Hydropropulsion 



ao4 



2.0 2,2 



Fig. 31 - IR-F powerplant performances: (a) rj^; , ,, 

 (b) (^= 0.9, p = 12, a. p.) 



only apparently surprising how the combustion of fuel into the compressed air 

 (that can be realized without any mechanical complexity) could raise strongly 

 the performances, since a qualitative argument in this way was the base of the 

 present work. 



(c) The increase of the turbine compression ratio /? moderately im- 

 proves the efficiency in the range of interest (Fig. 34), and this improvement is 

 magnified at higher speed. The values plotted in all the other diagrams corre- 

 spond to /3 = 12, which can be considered a good compromise between per- 

 formances and simplicity, but it is easy to ensure that values to /3 = 8 do not 

 change the performances sensibly. 



(d) The pumpjector is operatively poor in the configuration IB-(l) 

 (Fig. 37), since the operative speed field is very restricted, because the chamber 



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