Carnot cycle (8) S.J.T.0. Phase Transformation and Applications Isothermal Adiabatic Isothermal Adiabatic A->B B->C C->D D->A ∑ C(T-T)<0 C(T2-T)>0 W -RT In V20 RT In Rt-Z)n点<0 g RT In V2>0 0 RT In V0 0 :-7m长0 △U 0 C(T-T)<0 0 C(T2-T)>0 0 2+9 =0 SJTU Thermodynamics of Materials Fall 2012 X.J.Jin Lecture 4 Second law llPhase Transformation and Applications S. J. T. U. SJTU Thermodynamics of Materials Fall 2012 © X. J. Jin Lecture 4 Second law II Carnot cycle (8) W ln 0 3 4 1 < V V Q ln 0 RT 1 2 2 > V V RT ln 0 1 2 − 2 < V V RT ΔU 0 A->B B->C C->D D->A 0 Isothermal Isothermal Adiabatic Adiabatic ln 0 3 4 − 1 > V V RT 0 0 CV (T1 −T2 ) < 0 CV (T2 −T1) > 0 CV (T1 −T2 ) < 0 CV (T2 −T1) > 0 Σ 0 ( )ln 0 1 2 1 − 2 < V V R T T ( )ln 0 1 2 2 − 1 > V V R T T Q2 Q1 0 1 1 2 2 + = T Q T Q 4 3 1 2 V V V V =