2b(x) = 0.60 X +2b 



(9) 



where 2b(x) is the width of the jet (Figure 22) and 2b is the nozzle 

 width. Now, the momentuiiij M., of the jet, which is constant along the 

 jet is given by 



4 2^ ^ 

 M = ^ p U (x) 



xh 



(10) 



Since the axial momentum of the jet remains constant along x, thus 

 M expressed in Equation (6), which relates the power jet momentum 

 M to the momenta of active and passive leg flows, must be equal to 

 M. , i.e., (M- = M ). Hence, from Equations (6) and (10) the following 

 expressions results 



U(x) hVxw 



4 



(11-a) 



By defining 



U(x) h /xw 



(U-b) 



Equation (11-a) can be reduce to 



(11-c) 



with the active and passive leg flow parameters. A solution cf 

 Equation (11-c) is shown in a plot of Figure 23, where the diii-,3nsionless 



parameter 



U(x) 



is plotted against 





This result is used in locating the output ports of the amplifier. 



Finally the power jet flows into the output ports in proportion 

 to the deflection of the jet. Proper location and size of the mtput 

 flow passages is very important. Now a procedure for designing the 

 output ports of the amplifier will be given. A general layout c ' the 

 output port geometry is shown in Figure 24. Notice that points ', B 



13 



