Question

An ideal Brayton cycle with regeneration has a pressure ratio of 10. Air enters the compressor at 300 K and the turbine at 1200 K. If the effectiveness of the regenerator is 100 percent, determine the net work output and the thermal efficiency of the cycle. Account for the variation of specific heats with temperature.

Answer 1

η = 87.05 %

Step-by-step explanation:

Given that

Pressure ratio r= 10

T₁=300 K

T₃=1200 K

We know that ,for air γ = 1.4

As we know the efficiency of Brayton cycle when regeneration given as

`\eta=1-(T_1)/(T_3).r^{(\gamma-1)/(\gamma)}`

Now by putting the values

`\eta=1-(T_1)/(T_3).r^{(\gamma-1)/(\gamma)}`

`\eta=1-(300)/(1200)* 10^{(1.4-1)/(1.4)}`

η = 0.8705

η = 87.05 %