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of the flowing parts of the turbine that is flowed gases with high velocities. In the heat
exchanger speed gases less, so the rate of erosion less.
Secondly, the closed-cycle GTE work fluid pressure can be significantly higher
then atmospheric before compressor. This allows to significantly reducing the size of
compressor, turbine and heat exchanger.
Thirdly, the combustion in the combustion chamber of the gas turbine closed type
can be arranged in such a way as to minimize environmental pollution.

3. PARAMETERS OF A WORKING FLUID AT THE CHARACTERISTIC

3.1 For the calculation it is assumed that the state of the working fluid (WF) is
described by the equation of an ideal gas state and the heat capacity WF does not
depend at a temperature. Therefore, the unknown value of one of the thermal parameters
of the working fluid (P,V,T) can be determined from the equation of an ideal gas state
when the three values are known.

3.2 The relationship between the parameters of the working fluid at the start
(P s,V s,T s) and at the end (P e,V e,T e) adiabatic compression process WF is determined by
the ratios:

k 1
T  P  k

e T s   e P s  (3.1)

k 1 
T e   s   (3,2)

T 
s  e 
k
P  
e   s  (3.3)
P 
s  e 

The adiabatic constant k for these formulas depends from which gas is the working
fluid (see Appendix a). These formulas can be used to determine the parameters of the
WF in the process of adiabatic expansion. For isobaric process parameters RT is
determined from the equations:

 T 
s   e  (3.4)
 T
e  s 

and the change of entropy:

T 
s  C ln  e  (3.5)
pm T
 s 
where C pm - the average specific heat capacity at a constant pressure, kg J К 

3.3 Determination of the average specific heat capacity at a constant pressure.

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