绝热过程方程 dw=-Padv M Ckndt pdv+vdP= My RaT 消去dT,有 pd C RPdv=Cy mpdv +Ck mvdP Pdv+vdP (Cr,m + r)pdv+Cr,vdP=0 P dp dv 0 CVm+REc P.m P hP+vhy=常数P=常数国绝热过程方程 RdT M M PdV VdP m dW = −PdV + = 消去 dT ，有 R C PdV VdP PdV V ,m = + − − RPdV = CV ,m pdV + CV ,m VdP (CV ,m + R)pdV + CV ,m VdP = 0 V m P m C C , ,  = + = 0 V dV P dP  ln P + lnV = 常数或 =  PV 常数 CV ,m + R = CP,m C dT M M V m m =