with Variable Specific Heat of Working Substance. 171 

 where v 



v i 

 and T 3 = a/ ,7T(l + xTl-rr- 1 + «^r- 1 - a/3 r)... 



=*^T(1 + XE), (5) 



where H-Tfl-rT-l + ^y-l-^). 



Substituting (2), (3), (4), and (5) in (1), and neglecting 

 powers of X higher than the first, the efficiency bcomes 



V 





*f* ^"-l + ayfc-l)} 



-(^-1)^-1-1)- ^;^^) }, (6 ) 



where W = efficiency of the Dual Combustion Cycle assuming 

 Constant Specific Heat 



-I. X f ^ y -l 1 



7-7-1 (a-l + rya^-l)/ ' 



If p = l,as in the Constant Volume Combustion Cycle 

 "the expression becomes ' 



where , 1 



= Constant Volume Combustion Cycle effi- 

 ciency with Constant Specific Heat. 



If a =l as in the Constant Pressure Combustion Cycle 

 then J ' 



*"** 2 7 rr- 1 (p-l) I pr-1 



^ (py _ 1) + 2( rr-i_ 1) _rr^±l)j ?> _ (8) 



where 77/ = efficiency of Constant Pressure Combustion Cycle 

 with Constant Specific Heat 



= 1 1 f y ~l 



In (7) and (8) the coefficients of the term XT in each case 



N 2 



