# Difference between revisions of "Kees' assignment"

From Interactive System for Ice sheet Simulation

(→Model equation: fixed absolute value issue) |
(→Numerical tips: generalized to arbitrary n) |
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Use a staggered grid such that the <math>D(x_{j+1/2})</math> are computed at the '''centers''' of the grid (as opposed to the vertices, as we have been doing), so | Use a staggered grid such that the <math>D(x_{j+1/2})</math> are computed at the '''centers''' of the grid (as opposed to the vertices, as we have been doing), so | ||

− | :<math>D(x_{j+1/2}) = C \left(\frac{H_j + H_{j+1} | + | :<math>D(x_{j+1/2}) = C \left(\frac{H_j + H_{j+1}}{2}\right)^{n+2} \left(\frac{h_{j+1} - h_j}{\Delta x}\right)^{n-1}.</math> |

From the diffusivity, the flux is computed | From the diffusivity, the flux is computed |

## Revision as of 13:13, 5 August 2009

## Contents |

## Model equation

where

and

## Model parameters

- km/yr
- = 920
- g=9.8
- A = 1e-16
- n=3

## Boundary conditions

- (left boundary)

- (right boundary)

## Numerical tips

Use a staggered grid such that the are computed at the **centers** of the grid (as opposed to the vertices, as we have been doing), so

From the diffusivity, the flux is computed

- ,

where

and then the flux () can be used to compute the rate of change of the surface from