Hello, nice to meet you. I've been working with multiple soil properties, varying the bulk density of the samples and therefore changing the soil hydraulic parameters. I am working with the van Genuchten-Mualem hydraulic model, the single porosity model. However, I've been experiencing convergence issues for values of n [-] greater than 2.5, for example. Could you give me some insight or comment on the reason for this problem? Thank you.
Best regards
Jorge R.
Convergence problems for values of n greater than 2.5
Re: Convergence problems for values of n greater than 2.5
High values of n (typical for sandy soils) make the soil hydraulic properties highly nonlinear, with sharp moisture fronts and low water retention (the residual water content is reached for low pressure heads). This typically requires finer spatial and temporal discretization, and using lower values for hCritA and the wilting point (for root water uptake). J.
Re: Convergence problems for values of n greater than 2.5
Thank you very much, Jirka. Problem solved. Best regards and success.