problem with the time step jump in an LES (transient) study
I am running an LES study for a periodic pipe unit which has helical grooves around its periphery.
Although, I know the results have not converged so far, I did wanted to ask about a jump in time step/flowtime that I have observed in the report file that I create.
One of my wall temperatures reports have the following resutls with
time-steps ----wall temperature ------flow time
1185 300.01324 0.00473999999999
2439 300.33120 0.009755999999999
Below and above these two numbers is a 1 time step increase (.....1183, 1184 and 2349 , 2340, 2341 ...... etc), except in the above shown result.
I have the following commands for saving of time steps and others.
/solve/set/cfl-based-adaptive-time-stepping yes no 1 1 0.000004 100 1 , , , ,
My guess is this jump is because of the cfl-based-adaptive-time-stepping yes command that I have. And as a consequence if I try to plot the wall temperature vs time step(or) flow-time, I get a discontinious graphs.
Is that the case why I have this jump in the time step? Or is there an another reason?
Also, adaptive time stepping for cfl seems a nice feature, so should it always be used?. Or more importantly, when should it be not used?