Transcript Main Thermo Formulas

General Conservation Law(s)
For any property P: mass, energy, entropy, availability…:
Property ACCUMULATI ON
P
t CV



p (  dV ) 

t Control
[CV Accumulation]rate=
Volume
=[(In-Out)CS + (Production-Destruction)Sys]rate
 [In-Out]rate=
PIn Out
Property TRANSPORT
 





   p flux  dA   p (  U  dA)
Control
Surface
Control
Surface
 [Accumulation]rate= 0 for a steady flow process
 [(Production-Destruction)]rate = 0 for mass and energy
 [Production =s] rate  0 for entropy; [Prod.=SF] rate for momentum
 [Destruction =I =T0s] rate  0 for availability (exergy)
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Property TRANSFER