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(Created page with "This is a page for setting up pages before loading them. The discretized momentum equations are <math> U_{i,P}^{n+1} = \frac{1}{a_{i,P}} \biggl( \sum_{k=1}^N_{face} a_{i,k} U_...")
 
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This is a page for setting up pages before loading them.
This is a page for setting up pages before loading them.


The discretized momentum equations are
<math> \int\limits_{A}{\nabla \cdot \left( {{\Gamma }^{\phi }}h\nabla \phi  \right)}\text{d}A=\oint\limits_{S}{{{\Gamma }^{\phi }}h\left( \nabla \phi \cdot \mathbf{n} \right)}\text{d}S=\sum\limits_{f}^{{}}{\bar{\Gamma }_{f}^{\phi }{{{\bar{h}}}_{f}}\Delta {{l}_{f}}{{\left( {{{\hat{n}}}_{i}}{{\nabla }_{i}}\phi  \right)}_{f}}} </math>


<math> U_{i,P}^{n+1} = \frac{1}{a_{i,P}} \biggl( \sum_{k=1}^N_{face} a_{i,k} U_{i,k}^{n+1} + S_{i} \biggr)  
First the momentum equations are rewritten as
- \frac{h_P}{a_{i,P}} \sum_{k=1}^N_{face} n_i n_k  \Delta s_k p_k^{n+1}
{{Equation| <math> \frac{\partial ( h U_i ) }{\partial t}
+ \frac{\partial }{\partial x_j} \biggl( (h U_i U_j )-  \nu_t  h \frac{\partial U_i }{\partial x_j} \biggr)
= - g h \frac{\partial \eta }{\partial x_i} + S_i
</math>|2=1}}
 
where <math>S_i</math> includes all other terms. The equation is then integrated over the a control volume as
{{Equation| <math> \frac{\partial  }{\partial t} \int_A h U_i dA
+ \oint_F \frac{\partial }{\partial x_j} \biggl[ (h U_i U_j) -  \nu_t h \frac{\partial U_i }{\partial x_j} \biggr] dF
= - g h \oint_F \frac{\partial \eta }{\partial x_i} dF + \int_A S_i dA
</math>|2=2}}
 
The resulting di
 
 
<math> U_{i,P}^{n+1} = \frac{1}{a_{i,P}} \biggl( \sum_{k=1} a_{i,k} U_{i,k}^{n+1} + S_i \biggr)  
- \frac{h_P}{a_{i,P}} \sum_{k=1} n_{ik} \Delta s_k p_k^{n+1}
</math>
</math>


where the subscript <math>k</math> indicates the cell face, <math>p = g \eta</math> with <math>\eta</math> being the water surface elevation, <math>n_i</math> is the unit vector in the <math>i</math> direction, and <math>n_k</math> is the unit vector normal to the cell face.
The continuity equation is discretized as


The coefficient a_{i,P} is equal to <math> a_{i,P} = \sum a_{i,k} + a_P^0 </math>
<math> h^{n+1} -  \mathbf{S} </math>
 
 
where the subscript <math>k</math> indicates the cell face, <math>p = g \eta</math> with <math>\eta</math> being the water surface elevation, <math>n_{ik}</math> is equal to the dot product of the velocity unit vector and the cell face unit vector.
 
The coefficient <math>a_{i,P}</math> is equal to <math> a_{i,P} = \sum a_{i,k} + a_P^0 </math>


The continuity equation is discretized as
The continuity equation is discretized as
<math> p_P^{n+1} = p_P^n - g \frac{\Delta t}{\Delta A_P} \sum_{k=1} n_k F_k^{n+1}</math>
where <math>n_k </math> is the dot product of the cell face unit vector and


The depth-averaged 2-D continuity and momentum equations are given by
The depth-averaged 2-D continuity and momentum equations are given by
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for  <math>  j=1,2  </math>
for  <math>  j=1,2  </math>
{{Equation| <math> \frac{\partial ( h U_i ) }{\partial t} + \frac{\partial (h U_i U_j )}{\partial x_j}
- \epsilon_{ij3} f_c U_j h = - g h \frac{\partial \eta }{\partial x_i}
- \frac{h}{\rho_0} \frac{\partial p_a }{\partial x_i}
+ \frac{\partial }{\partial x_j} \biggl ( \nu_t  h \frac{\partial U_i }{\partial x_j} \biggr )
+ \frac{\tau_i }{\rho}
</math>|2=2}}

Latest revision as of 19:00, 17 March 2011

This is a page for setting up pages before loading them.

First the momentum equations are rewritten as

  (1)

where includes all other terms. The equation is then integrated over the a control volume as

  (2)

The resulting di


The continuity equation is discretized as


where the subscript indicates the cell face, with being the water surface elevation, is equal to the dot product of the velocity unit vector and the cell face unit vector.

The coefficient is equal to

The continuity equation is discretized as

where is the dot product of the cell face unit vector and


The depth-averaged 2-D continuity and momentum equations are given by

  (1)

for