复旦大学：《热力学与物理统计》课程教学课件（PPT讲稿）第二章 均匀物质的热力学性质

第二章均匀物质的热力学性质 1.基本热力学函数 2.麦氏关系及应用 3.气体节流和绝热膨胀

第二章 均匀物质的热力学性质 1. 基本热力学函数 2. 麦氏关系及应用 3. 气体节流和绝热膨胀

§21基本热力学函数 1.内能 dU=TdS-pdk U=U(, v),dvs/aU aU ds+ dy aU aU =7(S,V)2p p(S,v) S a-U aT ap avas aSa O aS

§2.1 基本热力学函数 1. 内能 dU = TdS − pdV V V U S S U U U S V U V S ( , ), d d  d         +        = = ( , ), p(S,V) V U T S V p S U T V S  =         = = −        = S V U V S U    =    2 2 S S V p V T          = −       

2.焓H=U+p dh=Tds+vd H=H(S, P),dHa aH ds+ T=/OH aH T(S, P), v V(S, p) a OH aT as aSap aS

2. 焓 dH = TdS +Vdp p p H S S H H H S p H p S ( , ), d d d            +        = = ( , ), V(S, p) p H T S p V S H T p S =            = =        = S p H p S H    =    2 2 H =U + pV S S p V p T         =          

3.自由能F=U-7S dF=-SdT- pdy F=F(T,V), dF_OF OF dT+ dT OT aF aF S s(T,V),p= T. aT 02F02F aS ap ovat aTaV aT OF OF OF U=F+TS=F H=U+ pV=F aT aT

3. 自由能 dF = −SdT − pdV T V F T T F F F T V F V T ( , ), d d  d         +        = = ( , ), ( , ) V T F F S S T V p p T V T V       = − = = − =           T V F V T F    =    2 2 F =U −TS T V F U F TS F T         = + = − V V T F V T F H U pV F T          −        = + = − T T V p V S          =       

4.吉布斯函数(自由焓)G=H-7S=F+p dG=-SdT+vdp G=G(,p),dG=/oG aG dtt dp aT P aG aG S =S(T,p)2 y(T, p) aT P丿 a2G aG aS apot oTop aT H=G+TS=G-TaG G aG U=H-pV=G aT OT

4. 吉布斯函数（自由焓） dG = −SdT +Vdp p p G T T G G G T p G p T ( , ), d d d            +        = = ( , ), V (T, p) p G S T p V T G S p T =            = =        = − T p G p T G    =    2 2 G = H −TS = F + pV T p G H G TS G T         = + = − p T p G p T G U H pV G T            −        = − = − T T p V p S         = −          