Evaluate the specific volume of heptane for T_r = 1.1 and P_r = 3.5 using(a) The van der Waals equation of state (T_c = 540.13 K, P_c?= 27.36 bar);(b) The generalized compressibility chart of Figure 6.6;

(c) TPSI. Which is more accurate among the values obtained with (a) and (b)? Consider the flow of 5 kg/s heptane in these thermodynamic conditions through a circular pipe. The flow velocity must be lower than or equal to 2 m/s in order to limit the friction losses over the long pipe. Calculate the pipe cross-sectional area using the Van der Waals equation of state and TPSI. What is the consequence of using an inaccurate thermodynamic model?

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Z=Pv/RT 1 0.8 0.6 0.4 0.2 0 T₁=1 1 T, 1.1 2 T, 1.5 T, 1.3 =1-24 T₁ = 21 3 Pr 4 5 6 7