Zero flux at boundaryZero flux at boundaryhttps://oss.deltares.nl/c/message_boards/find_thread?p_l_id=1806675&threadId=29824042020-07-12T02:46:48Z2020-07-12T02:46:48ZZero flux at boundaryMoein Doostmohammadihttps://oss.deltares.nl/c/message_boards/find_message?p_l_id=1806675&messageId=29824032020-05-15T15:37:06Z2020-05-15T15:37:06ZDear everyone,<br />i'm trying to model an estuary. I have water level datas for two of my boundaries but at the third boundary i don't have any data available,therefore i defined the third boundary as Neumann (the last two boundaries are perpendicular to each other). However i don't completely understand how neumann boundary condition works in Delft3D and how it affects the model. I specified the inputs as 0,0 for the begin and end field for both the start and the last time of simulation but i recognized some disturbances at the boundary. So the question is how am i supposed to define a zero-flux condition for my boundary?<br />I also tried inputs such as 0.1 and 0.001 for all fields in neumann flow conditions, but faced with water level changing too high or flow exited abnormally errors! now i rally fell dazed.<br /><br />Hope for your precious advice.<br />Best, MoeinMoein Doostmohammadi2020-05-15T15:37:06Z