Drag coefficients and obstacles

[vmarin@antar.ciencias.uchile.cl]

Greetings,

We are modelling the effect of water vegetation (macrophytes) on the concentration of suspended solids in a Chilean wetland. For MOHID the vegetation is simulated as polygons affecting the water flow as obstacles, using drag coefficients obtained from the literature. However, we are experiencing an interesting problem: if we use drag values up to 0.15 the model runs ok. If we increase it say to 0.19, the model crushes and generates a fortran error 65. Question: is there a limit to the drag value that can be used within the polygons?


Thanks in advance,

Víctor Marín