Question

Find the specific work in the case the volume is reduced. Saturated vapor R-134a at 50°C changes volume at constant temperature. Find the new pressure, and quality if saturated, if the volume doubles. Repeat the question for the case the volume is reduced to half the original volume.  

Answer 1

R-134a      50°C

v₁ = v_g = 0.01512 m³/kg, v₂ = v₁ / 2 = 0.00756 m³/kg

₁W₂ = ∫ PdV = 1318.1 kPa (0.00756 – 0.01512) m³/kg = -9.96 kJ/kg