Pallabazzer 



It appears also that A/A^— > oo when x^ — oo, meaning that during the expansion 

 the gas dilates more than the two- phase mixture. In Fig. (12), a is plotted 

 against A^/A^, and in Fig. (13), \- is represented as a fvmction of v^, m^^, 

 and /3„. 



Fig. 12 - Variation of X- 

 as a function of V^ for 

 some values of M^^ and 

 8(1^ = 0.9, a. p.) 



To sum up, the following remarks can be made: 



(a) There is a typical velocity v„ , below which any positive value of 

 ^i is detained asymptotically; the pseudo- Mach number at the exit has a limit 

 at M^j = M'J, where \-^ becomes infinite. There are no physical but just sonic 

 limits. At a velocity above v^, a maximum in the pseudo- Mach number is 

 reached at x^ = k[, but x^ still increases asymptotically as M^ decreases 

 to M'.'. 



(b) v„ corresponds to 30 m/s for / 

 while it decreases strongly at increasing /3^ 



p = (that is for the hydrojector) , 

 and becomes zero for /S = 4.3. 



This means that the hydrojector at a speed above 30 m/s will tend to be un- 

 suitable for reaching the highest performances; at increasing /S^ the physical 

 threshold advances but the value of \} decreases at increasing /Sp and at in- 

 creasing speed (Fig. 10), becoming insensitive to the speed at the highest /3p. 



1124 



