User:Xenomancer/PowerGen

Some power generation thermodynamic cycles

Closed Brayton Cycle with Gas Dissociation

A gas dissociation modification of the closed Brayton cycle using the gas phase NO2/N2O4 system as the working fluid.

Reactions and Kinetics

Reaction Equilibria

Where $A=N_{2}O_{4}$ and $B=NO_{2}$

• Heating CSTR: $A\rightleftharpoons B$, $\Delta H_{rxn}^{o}={\dot {Q}}_{rxn}^{o}$
• Cooling CSTR: $2B\rightleftharpoons A$, $\Delta H_{rxn}^{o}=-{\frac {{\dot {Q}}_{rxn}^{o}}{2}}$

Rate Expressions

• Heating CSTR: $-r_{A,2}=k_{f}^{o}{\text{exp}}{\left({{\frac {\Delta E_{f}^{o}}{R}}{\left({{\frac {1}{T^{o}}}-{\frac {1}{T_{2}}}}\right)}}\right)}C_{A,2}-k_{r}^{o}{\text{exp}}{\left({{\frac {\Delta E_{r}^{o}}{R}}{\left({{\frac {1}{T^{o}}}-{\frac {1}{T_{2}}}}\right)}}\right)}C_{B,2}^{2}$
• Cooling CSTR: $-r_{B,4}=k_{f}^{o}{\text{exp}}{\left({{\frac {\Delta E_{f}^{o}}{R}}{\left({{\frac {1}{T^{o}}}-{\frac {1}{T_{4}}}}\right)}}\right)}C_{A,4}-k_{r}^{o}{\text{exp}}{\left({{\frac {\Delta E_{r}^{o}}{R}}{\left({{\frac {1}{T^{o}}}-{\frac {1}{T_{4}}}}\right)}}\right)}C_{B,4}^{2}$

Mass Balances

Heating CSTR

Start with a standard CSTR balance:

$V_{H}={\frac {F_{A,1}X_{H}}{-r_{A,2}}}$