option to use vertical diffusion only in T3D
OPTDIF = 2 is deleted from v8p5.
It is proposed to reimplement this issue described in BREUGEM, W. Alexander. Ongoing developments in TELEMAC and TOMAWAC at IMDC. Online proceedings of the papers submitted to the, 2020, 115-121..
The method is: -solve advection -solved vertical diffusion and eventual vertical advection (as rising or settling velocity; the default value is zero) with a modified version of setdif.f, which also includes free surface boundary conditions, and explicit and implicit source terms.
- do not solve the diffusion using the linear equation
Note that the effect of the horizontal diffusion in practise is typically quite limited, because the advection schemes in TELEMEAC has quite some numerical diffusion.
The advantages of this method -fully mass conservative (as horizontal diffusion leads to mass balance issues) -substantially faster (as no linear system has to be solved)
@chi-tuan.pham Do you have an idea which of the existing test cases would be good to use for this functionality.