setting up Hot Start file

[Joe S.]

Are there any past forum discussion on setting up a hot start file?
I did not find anything in forum. And I did a quick search of various User Manuals, without any documentation found.

Under Unsteady Flow Analysis, set output control options, there is the RESTART FILE tabs. Do I run this hotstart for 1 hour, to establish my initial conditions. Then do I COMPUTE for the exact same time duration?
____________________________________
errors:
Performing Unsteady Flow Simulation HEC-RAS 5.0.1 April 2016

**** ERROR: Solution Solver Failed ****

Unstable for Initial Iteration at 16MAY2016 0100

**** The Model Has One Or More Error(s) ****

Unsteady Flow Simulation Terminated

Writing Results to DSS

Error with program: RasDSSWriter64.exe Exit Code = 1

[PaoloP]

Joe,
it is not clear to me.
Did you create an hot-start file and the model crash when you use this hot-start or the model crash when you are running the model to create the hot-start?

Paolo

[Joe S.]

the error happens without a hot start, and even after I tried to make a hot start file. I might not be creating the hot start correctly.

[PaoloP]

Joe,
usually the hot-start is used to continue previous simulation or to create the initial condition when the model is complex or unstable for low discharge using the steady state initial condition.
In the last case you have to run a simulation starting with initial conditions those are stable and decrease the flow up to the discharge you want to use as initial condition for your simulation and than save the hot-start. Obviously the simulation must be stable, if not you have to change something in the geometry.
Paolo

[Author]

Posts