Personal tools

Difference between revisions of "Biharmonic"

From MohidWiki

Jump to: navigation, search
Line 6: Line 6:
  
 
<math>\kappa_4 \sim \frac{U}{16} \Delta x^3</math>
 
<math>\kappa_4 \sim \frac{U}{16} \Delta x^3</math>
 +
 +
where U is a typical flow velocity and <math>\Delta x</math> is the numerical model horizontal resolution.
  
 
==References==
 
==References==
 
  Delhez, E., & Deleersnijder, E. (2007). Overshootings and spurious oscillations caused by biharmonic mixing.  
 
  Delhez, E., & Deleersnijder, E. (2007). Overshootings and spurious oscillations caused by biharmonic mixing.  
 
  Ocean Modelling, 17(3), 183-198. doi: 10.1016/j.ocemod.2007.01.002.
 
  Ocean Modelling, 17(3), 183-198. doi: 10.1016/j.ocemod.2007.01.002.

Revision as of 15:18, 28 June 2011

The biharmonic coefficient is an extra term that is added to the horizontal turbulent viscous flux, J:

\mathrm{J} = -\mathrm{K}\cdot \nabla C + \nabla_{h}\left( \kappa_4 \nabla_{h}^2 C \right)

A ready made formula that would estimate the order of magnitude of the k_4 coefficient would be

\kappa_4 \sim \frac{U}{16} \Delta x^3

where U is a typical flow velocity and \Delta x is the numerical model horizontal resolution.

References

Delhez, E., & Deleersnijder, E. (2007). Overshootings and spurious oscillations caused by biharmonic mixing. 
Ocean Modelling, 17(3), 183-198. doi: 10.1016/j.ocemod.2007.01.002.