- #1
gfd43tg
Gold Member
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When you have energy going through a plane wall, I know that the heat flow rate should be constant, meaning what comes in should go out. But is this true even if it is transient, and a non-steady state process?
I think the energy content of the plane will not change for steady state, but for transient it will change, because there is an accumulation of energy term in the balance that is non-zero.
##\frac {dE}{dt} = \dot Q_{x} - \dot Q_{x+\Delta x} + \dot e_{gen}A \Delta x##
Maybe I should clarify. If the internal heat generation were zero, but ##\frac {dE}{dt}## was non-zero, would the energy content of the plane wall change?
I think the energy content of the plane will not change for steady state, but for transient it will change, because there is an accumulation of energy term in the balance that is non-zero.
##\frac {dE}{dt} = \dot Q_{x} - \dot Q_{x+\Delta x} + \dot e_{gen}A \Delta x##
Maybe I should clarify. If the internal heat generation were zero, but ##\frac {dE}{dt}## was non-zero, would the energy content of the plane wall change?