For the case of fixed-support end condition, it has been shown 

 analytically (Ref 12) that an increase in implosion strength on the order 

 of 6% can be expected. The implosion pressure can be calculated for 

 this case by using the equations presented herein and a reduced cylin- 

 der length of 0.85L. 



Long Cylinders . The expressions to predict implosion pressure for 

 long cylinders were developed as follows . 



Equations 9 and 10 are substituted into Equation 8 to yield: 



910 1^^' 



1 + 690 f |- 

 o , 



(13) 



Once the stress level at implosion is calculated, the same condi- 

 tions as for moderately long cylinders hold; that is: 



(a) If a. /f > 1.0, thick-wall analysis is used to predict 

 implosion. Equation 3 



(b) If 0.52 < a. /f < 1.0, then n is calculated by Equa- 

 tion 10 



(c) If a. /f < 0.52, then n = 1.0 



mi c ' ' 



If steps (b) or (c) control, the following expression, which was 

 developed by substituting Equations 8 and 9 into Equation 1, predicts 

 the implosion pressure: 



p,^ = 1100 n fl (^-'l (14) 



im ' c I D 



19 



