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The average heat capacity in a given temperature range is determined by the truth
specific heat capacity at a constant pressure according to the formula [4] (Appendix B)

2 T 2 T
C  1 T T  C dT (3.6)
pm 2 1  p
1 T 1 T
where T 1 - the range of temperature change ;
C p - true heat capacity, which can be determined from the dependence:

С p = а + b(T/100) + d(T/100)² + e(T/100)³ , (3.7)
where a, b, d, e are coefficients of the functional dependence of the true heat capacity of
the gas absolute temperature (see Appendix B)

In general, the average molar isobaric heat capacity is determined from the formula

 T  T    b   T  2 T  2  
a
  3 100    1 100       3 100    1 100    

3 T 1        2        
C    (3.8)
 pm T T 3 3 4 4
1 T  3    1    d   T 3   T 1     e   T 3   T 1   



 100   100      100   100      100   100   
  3         4        

The average specific heat at constant pressure is determined from the molar isobaric
heat capacity
C
C  pm (3.9)
pm

where µ is the molecular mass of gas.

3.4 After determining of the WF parameters at the key points of the cycle we build
working and heat charts.

4. CHARTING BRITON’S CYCLE

4.1 The thermodynamic cycle of the gas turbine with regeneration heat is plotted in the
coordinate system of v , P and s, T.

4.2 The scales on the coordinate axes should be taken so that the length and the height
was in the range of 90-150 mm.

4.3 After selecting the scale (they can be different for different axes) it is necessary to
inflict division on the axles evenly dividing. Then on the working diagram to put
characteristic points of the cycle (1, 2, 3, 4) values of the specific volume and pressure
of the WF. The relation (3.3) is used to build the adiabats. It is necessary to take at least
ten points in the interval [ 1, 2] and in the interval [ 3, 4]. The results of the calculation
should be put in tabular form.

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