化工热力学国际班ch.pptx

Chapter 3 Thermodynamic Properties of Fluids流体热力学性质 ;The 2nd Law:;3.1 Property Relations for Homogenous Phases;For isobaric process：;For T and P changing process：;For T and P changing process：;The Maxwell Eqn;Relations between thermodynamic functions ;For ideal gas：;For ideal gas：;3.3 Residual Properties 剩余性质;Available for HR , SR and VR calculations.;For ideal gas:;is the only function of T ：;3.3.1 Calculate HR and SR from experimental data ; Ex;Solution：; P(MPa) ;P(MPa) ;Then :;3.3.2 Calculate HR and SR with Cubic EOS ;With R-K eqn：;Differentiate R—K eqn with respect to T at constant V：;;Ex 3.1. ;Calculate h and A/B :; 3.3.3 Generalized Correlations for HR and SR of Gases 气体热力学性质普遍化关联;Calculate H and S from generalized correlation graph 由普遍化关联图求焓与熵 ;Calculate each term at different Tr and Pr, and get generalized correlation plot.;;;p42;;;3.3.4 Calculate H and S with generalized virial correlation 由普遍化维里系数计算焓与熵 ;普遍化第二维里系数关系式适用区域 p21;When a system changes from state 1 to state 2 ：;Ex. 3.3;;;H and S: （a）vaporization at T1and P1 （b）convert to ideal gas at T1 , P1 （c）ideal gas T1,P1 to T2,P2 （d）convert to real gas at T2 ,P2 ;（a）;Find A and B from boiling point and critical point： ;;( c）ideal gas T1,P1 to T2,P2;Sum up the above 4 steps to give H and S： ;3.4 H and S calculation for liquids;Ex. 3.2 H2O (l), 25 ℃ and 0.1 MPa → 50 ℃ and 100 Mpa, DH & DS ?;;3.5 H and S calculation for vapor-liquid systems in equilibriem;T-S Graph for pure component ;Phase change;;c. Isentropic expansion;c. Isentropic compression： 1?2;re;Ex. ;H-S Graph 焓熵图 （Mollier-graph);P-H graph 压焓图;3.8 Tables of thermodynamic properties;Home Work