B,31 • DENSITY DIFFERENCES AND COMPRESSIBILITY 



clear that the reduced density corresponding to the higher temperature 

 causes a more rapid spreading of both the velocity and temperature pro- 

 files. Again the temperature profile is wider than the velocity profile. 

 Fig. B,31b shows the decrease of velocity and temperature along the axis. 



_5 _4 -3 -2 -1 



Fig. B,31a. Radial velocity and temperature distribution in round jet showing 

 effect of density, after Corrsin and Uberoi [123]. Section 16 nozzle diameters from 

 orifice. Ta = initial temperature of jet, Tc = temperature at center, Ti = temper- 

 ature of surrounding air. 



Fig. B,31b. Ajdsl velocity and temperature distribution at center of round jet, 

 after Corrsin and Uberoi [123]. x = distance from orifice, d = diameter of nozzle. 

 To = initial temperature of jet, Tc = temperature at center, Ti = temperature of 

 surrounding air. 



The decreased density causes both velocity and temperature to fall more 

 rapidly than for constant density. 



No appreciable change was noted in the shape of the profile in the 

 fully developed jet for pi/po = 2. Corrsin and Uberoi showed definitely 

 that there was no measurable change in the shape of the total head pro- 



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