Gas-Turbine Powerplants For Two-Phase Hydropropulsion 



has not been given to the thrust coefficient, in opposition to the current methods, 

 and an analysis based on the specific thrust has been preferred. 



Finally, as regards the hypothesis of an adiabatic gas expansion and its 

 consequences of overestimation of the efficiency of hot-gas injection and under- 

 estimation of the efficiency of cold-gas injection, I think the best one could ex- 

 pect from a theoretical provisional analysis is just to provide a couple of limit 

 conditions between which all practical cases take place. As I emphasized in 

 this paper, its aim is not to furnish exact solutions of the problem but just a 

 provisional comparative evaluation from which one could estimate the competi- 

 tive availability of a two- phase propulsor. 



The same reply can be addressed to the first remark of Dr. Quandt; one 

 must add also that the energy exchange between hot gas and water is not a 

 standard phenomenon, since it can be strongly influenced and shifted by a 

 geometry which must be studied purposely to reduce heat transfer. 



As regards the slip in a bubble flow, its effect is very feeble, in opposition 

 to the droplet flow, which has been considered by Dr. Quandt in his paper, 

 where the slip effect can be very strong. 



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