Gas Nuclei Trajectories and Cavitation Inception 



0.2 0.3 0.4 



VAPOR CAVITATION NUMBER - 



Fig. 7 - Upper and lower critical sizes of gas nuclei 

 as a function of vapor cavitation number and the body 

 size (U = 50 fps) 



Body Size Effect on the Incipient Cavitation Number 



In Fig. 7 the initial bubble radii are plotted versus vapor cavitation number 

 for a constant speed of u = 50 fps. There is one curve for the lower critical 

 bubble radii R*^ and this curve is the same for all body sizes as described 

 previously. In the same figure are eight curves for the upper critical bubble 

 radius; each curve refers to a specific body size. Therefore, for a given value 

 of a^ and for a free stream bubble population that includes all sizes, < Rg < », 

 Fig, 7 shows that only the range of bubble sizes R*^ < Rq < R*^ can actually 

 participate in the inception of cavitation, that is, become unstable. The 



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