1-Dfow:< Tis only the function of s.Φ=Φ(s) (d)mn=(Bdm)m=(pAds)im=(BpAVdt) In the like manner (d)out =(Bpavdtout 2 tt+at dd +-,[(dd)o-(a)m dt -+lBpADout-BpAl)in RTT For stead docy dd y (BpADout-BpADin flow dt( ) ( ) ( ) ( ) d dm Ads AVdt  = = = in in in in    In the like manner ( ) ( ) d AVdt  = out out  1 [( ) ( ) ] s cv out in d d d d dt dt dt   = +  −  [( ) ( ) ] cv out in d AV AV dt    = + − s 1-D flow :  is only the function of s .  = ( )s For steady flow : 0 d cv dt  = ( ) ( ) s out in d AV AV dt     = − t+dt t+dt t t ds R T T