[benmodra]

Hi,
I'm very new to numerical modelling but have a relatively simple problem to get started on. The application is discharge calculation of riverflow based on HorizontalADCP data that gives velocities in a line across the river at a single depth. The data is to be extrapolated to all depths in the cross-section, then integrated to give the total flow.

The methed I'm using is given in this paper:
http://www.rs.noda.tus.ac.jp/~hydrol...%26Kimizu).pdf
with finite difference solution having the following descretisation (sorry the image is not very clear):


However eddy viscosities are not made explicit in the paper, so my query is: how are the horizontal and vertical eddy viscosities (AH and AV) determined for this? I realise there are many turbulence closure solutions, but what is appropriate for this problem and relatively simple to implement?

Regards, Ben