[Lih]

I am trying to run a model using unsteady flows, and it is blowing up straight away with the error "Matrix Solution Failed" and "Minimum error exceeds allowable tolerance at 29DEC2005 2400"

what do these errors mean and what are likely causes/solutions?

I have trawled through the forums for potential solutions and have tried the following:

*I thought it might have been due to initial conditions. I matched up my initial flows to te start of the flow hydrographs.

*I incorporated pilot channels along pretty much the whole model length

*I tried to create a hotstart file, using steady flows in an unsteady flow file + initial water levels at each XS for the corresponding flows, sourced from steady flow model results. I even tried reducing it to just the one inflow at the top, and a constant WL at the bottom.

But I still get the same error...

For what it's worth the model is 35000' long with elevations from 55' to -15', it is quite uneven with many bridges and obstructions and 2 split flows. However I dont think the geometry is too relevant at this stage as the model is falling over straight away.

Any assistance appreciated!

Thanks