Nitrogen is compressed by an adiabatic compressor from 101 k

Nitrogen is compressed by an adiabatic compressor from 101 kPa and 20 degree C to 635 kPa and 224 degree C. Calculate the entropy generation for this process. S_gen = 0.061 kJ/kg middot K

Solution

Given

P₁ = 101 kPa

T₁ = 20^oC

P₂ = 635 kPa

T₂ = 224^oC

From refrigeration tables, for N₂ at P₁ = 101 kPa and T₁ = 20^oC, we have

specific entropy, s₁ = 6.8196 kJ/kgK

Similarly at P₂ = 635 kPa and T₂ = 224^oC

specific entropy, s₂ = 6.8361 kJ/kgK

Entropy generation

s_gen = s₂ - s₁ = 6.8361 - 6.8196 = 0.0165 kJ/kgK.........................(answer)