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STIRLING CYCLE (1827) AND ITS PROCESS

 The Stirling cycle consists of two reversible isotherms and two reversible isochores. For 1 kg gas ,

 Q1-2 = W1-2 = RT ln (v2 / v1)

 Q2-3 = Cv (T1 - T2); W2-3 = 0 

 Q3-4 = W3-4 = - RT2 ln (v3 / v4) 

 Q4-1 = Cv ( T1-T2); W4-1 = 0 



Due to heat transfers at constant volume processes, the efficiency of  the Stirling cycle is less than that of   the Carnot cycle. However, if a regenerative arrangement is used such that 

 Q2-3 = Q4-1 , i.e., the area under 2-3 is equal to the area under 4-1, then the cycle efficiency becomes 

 N = ( A - B) / A 

where,

N is the efficiency 

A= (RT1 ln (v2 / v1))

B = (RT2 ln (v3 / v4)) 


there fore , 

N = (T1 - T2) /  T1 

So, the regenerative Stirling cycle has the same efficiency as the Carnot cycle. 

   

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