Governing equations on differential form: Difference between revisions

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{{NumEqn|<math>
{{NumEqn|<math>
\frac{d}{dt}\iiint_{\Omega} \rho dV+\iint_{\partial \Omega}\rho \mathbf{v}\cdot \mathbf{n} dS=0
\frac{d}{dt}\iiint_{\Omega} \rho dV+\iint_{\partial \Omega}\rho \mathbf{v}\cdot \mathbf{n} dS=0
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em}}
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em|color=steelblue}}


Apply Gauss's divergence theorem on the surface integral gives
Apply Gauss's divergence theorem on the surface integral gives
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{{NumEqn|<math>
{{NumEqn|<math>
\frac{d}{dt}\iiint_{\Omega} \rho \mathbf{v} dV+\iint_{\partial \Omega} \left[(\rho\mathbf{v}\cdot\mathbf{n})\mathbf{v}+p\mathbf{n}\right]dS=\iiint_{\Omega}\rho \mathbf{f}dV
\frac{d}{dt}\iiint_{\Omega} \rho \mathbf{v} dV+\iint_{\partial \Omega} \left[(\rho\mathbf{v}\cdot\mathbf{n})\mathbf{v}+p\mathbf{n}\right]dS=\iiint_{\Omega}\rho \mathbf{f}dV
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em}}
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em|color=steelblue}}


As for the continuity equation, the surface integral terms are rewritten as volume integrals using Gauss's divergence theorem.
As for the continuity equation, the surface integral terms are rewritten as volume integrals using Gauss's divergence theorem.
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{{NumEqn|<math>
{{NumEqn|<math>
\frac{d}{dt}\iiint_{\Omega}\rho e_o dV+\iint_{\partial \Omega}\rho h_o(\mathbf{v}\cdot\mathbf{n})dS=</math><br><br><math>\iiint_{\Omega}\rho\mathbf{f}\cdot\mathbf{v}dV+\iiint_{\Omega} \dot{q}\rho dV
\frac{d}{dt}\iiint_{\Omega}\rho e_o dV+\iint_{\partial \Omega}\rho h_o(\mathbf{v}\cdot\mathbf{n})dS=</math><br><br><math>\iiint_{\Omega}\rho\mathbf{f}\cdot\mathbf{v}dV+\iiint_{\Omega} \dot{q}\rho dV
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em}}
</math>|nonumber=1|border=1|background-color=whitesmoke|padding=2em|color=steelblue}}


Gauss's divergence theorem applied to the surface integral term in the energy equation gives
Gauss's divergence theorem applied to the surface integral term in the energy equation gives