Question

Given: Air at 20 C and 100 kPa enters the first stage, and it exits the third stage at 6400 kPa. An inter-cooler is used to cool the air between the stages back to 20°C. The compression work per unit mass of air is γ-1 where γ is the specific heat ratio, R is the gas constant, subscript "i" denotes the initial (atmospheric) conditions, and subscript "o" signifies the exiting conditions. Find: intermediate pressures so that the total work is minimum, solve it using geometric programming: assume the compressions are reversible and adiabatic. Give the values of the minimum work and the two intermediate pressures

Answer 1

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