Problem 1.1 (a) Wi-fPdV=PV2. Next, to calculate Tf we note that from (i) to (f) we have
dM dt = m
du dt mh1
where in is the instantaneous flowrate into the cylinder, and M and U are the mass and energy inventories of the system (the "system" is the cylinder volume). Integrating in time,
Mr-M₁= mdt
U-U-PV2+h (M-M)
(1)
and recognizing that U₁ = 0 and M₁ = 0, the first law reduces to
UfMfh1-P1V2
(1')
For the "ideal gas" working fluid we write
Ur=Mfcv (Tr-To)
h₁=cv (T1-To) + PV1
hence, eq. (1') becomes
MFC (TTO)=Mf [cv (TTO) + PV1]-P1 V2
Noting that V2 =Mfvf and dividing everything by Mr yields
or
CvTf+P1 Vf c T + PV
cvTf+RTCT + RT
in other words, Tf=T1. The final ideal-gas mass admitted is
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