An improved numerical scheme for distributed hydrological models
Abstract
We propose a new high-resolution numerical scheme applying the CIP method to distributed hydrological models, which are often used in numerical simulations of floods, lava flows, and debris avalanches. The CIP method is a high-order upwind differencing scheme that can obtain a fine structure of flows with a relatively small number of calculation cells. However, this method is not always conserve the total value of a considered quantity because it is based on an advective equation of non-conservative form. It is desirable to improve the CIP method so as to exactly guarantee mass conservation, because the mass balance of water, for example, is an important index for flood simulations. For the reason, we propose a new numerical scheme that combines the CIP method with a flux-conservative equation. Numerical tests of the newly proposed scheme with simple conditions show that the results are as accurate as the results of original CIP method and exactly satisfy conservation law. The proposed scheme is very suitable for distributed hydrological models because the flows calculated by this scheme are little affected by the directions of calculation cells.
- Publication:
-
EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA.....2417I