Common Output Files

The output files produced will depend on the type of case you are running (steady flow solve, unsteady flow solve, optimization, etc.) This page will describe some of the general output files which are produced for almost all types of runs. For more specific output files and their contents, see the appropriate page, e.g. optimization output here.

Standard IO and General Output Files

Most of the standard IO is sent to one of two places:

• screen: Fortran standard IO is sent here (or whichever file is specified by #SBATCH --output=). This will contain run-time errors, as well as other general messages written by the code. If your run crashes or behaves unexpectedly, this should be one of the first places to look for the reason.
• SLURM error file: The name of this file depends on the run script variable #SBATCH --error=. Setting #SBATCH --error=%x.e%j names this file <jobname>.e<jobnumber>. SLURM messages, such as time out messages, usage info, etc, will get written to this file. Also, in some instances some standard IO error messages may get written here. Check this file if your job terminates unexpectedly.
• results.scr: This is a 'screen' file to which general user-readable information is printed. It contains an overview of what the job is doing, and will contain different information dependeing on the job type, but is a good place to look for errors, the current task the code is working on, etc.

Flow Solver Results Files

Most of Jetstream's general output goes to files called results.*. This is the default prefix, but it can be changed with the variable output_file_prefix. While just a subset, the most useful results files are:

• results.his: This is the steady flow solve convergence history file. It looks like

where:

• iter: Nonlinear iteration number
• time: Wall time for the flow solve
• res: L2-norm of the flow residual
• maxr2 max_node(4123): Five numbers giving the location of the maximum residual in the following order: rank, local block number, j-k-m node.
• maxres(1): Maximum mean flow residual
• kit: Krylov iteration count
• Cl, Cd, Cm: Lift, drag, and moment 'coefficients'. Note that these are not actually the coefficients, but rather the coefficients multiplied by the projected area.
• Sref: Projected area of geometry. Careful, it may not be your desired 'reference' area.
• res_turb: Maximum value of turbulence equation residual

This is the place to look to see if your solve has converged correctly, and if not some information on when/how it failed.

• results.solv: Detailed flow solver convergence history information. It shows what phase the solver is in, time step info, Krylov solver convergence history at each nonlinear iteration, etc. This file will have detailed information which can help diagnose why a solve failed. E.g. Are the Krylov solves not converging, did it fail in the start-up or inexact phase, was excessive damping applied, etc.
• results.tinfo: Convergence info for the turbulence model, including residual convergence and scaling vector data.
• results.q: This is the PLOT3D format binary file containing the solution, q. Together with the grid file it can be used to visualize the solution.
• results.t: A PLOT3D file with the turbulence solution in place of q, as follows. q(1) = laminar viscosity, q(2) = dimensional turbulence variable, q(3) = nondimensional turbulent viscosity, q(4) = vorticity, q(5) = turbulence residual.
• results.ldist: Spanwise lift distribution file (if requested). Careful, right now this makes some assumptions about block index directions. Talk to a senior lab member before trusting it.