得H=0622P P-Ps. 所以p4=0622+1 t>ta(t,)>ta 和空气 =ta (t=ta得 所以 不饱和空气 饱和空气 d d d s t s t s t P p p H , , , 0.622 − = d d d s t s t s t H H P p , , , 0.622 + = as w d t  t (t )  t as w d t = t (t ) = t