Control Panel Output Introduction
The Output panel enables you to control output generated by the CFD-ACE-Solver. These settings control the frequency of output and the contents:
• Output Options
• Printed Output
• Graphical Output
• Monitor Points Output-Output Options
Control Panel
Output-Output Introduction
The Output panel enables you to select the frequency with which the solver output is written.
Solver output includes graphical output data for visualization purposes, and model restart data to allow the simulation to be restarted at a later time. The Output panel contains:
• Steady State Simulation
• Unsteady Simulations
• User Defined Output - These activate the corresponding user subroutines: User Sub(uout), User Sub(uread_dtf), and User Sub(uwrite_dtf). See the User Manual-User Subroutines for more details.
Output Panel
The output options behave slightly differently depending on whether the simulation is steady or unsteady (transient).
Control Panel
Output-Output Options-Steady State Simulations
The pull-down menu next to Output Results enables you to output the results at the end of the run or at specified intervals. If you select specified intervals, you can enter the iteration frequency (results will be output after every iteration frequency interval).
The unique file option, if activated, will cause the solution output to be written to separate DTF files named modelname.####.DTF where #### is the iteration number. The last solution output dataset will be written to the original DTF file.
Control Panel
Output-Output Options-Unsteady Simulations
The Output Location pull-down menu outputs the results in one of three modes: Unique Filename, Unique Simulation, or Replace Simulation. If you are using the instant time-step option, then specify the frequency (in timesteps) to save the solution output. If you are using the automatic timestep option, then specify the time frequency to save the solution output.
Unique Filename
The Unique Filename option writes the solution output to separate DTF files. The files will be named as modelname.#####.DTF, where ##### is a timestep sequence number.
Unique Simulation
The Unique Simulation option writes the solution output to separate simulations in the same DTF file. You will only have one solution output file (modelname.DTF) but contained therein will be separate simulations for each timestep saved. Upon opening the DTF file in CFD-VIEW you can specify which simulation to load.
Replace Simulation
The Replace Simulation option writes the solution output to the DTF file by simply overwriting the last saved simulation. Use this method if you are running a transient problem to steady-state, or you do not care to retain the time history of your transient simulation.
Output-Printed Output
Control Panel
Output-Printed Output Introduction
The Printed Output panel enables you to activate boundary condition integral output, diagnostic output, and select one or more summary reports. It contains the following:
• BC Integral Output
• Diagnostics
• Residual Frequency
• Summary Reports
Output Panel - Print Tab Control Panel
Output-Printed Output-BC Integral Output
The BC Integral Output option allows the solver to integrate engineering quantities over selected boundary condition patches. For transient simulations, the time history of these integrated quantities will be written to the output file. Upon selecting the BC Integral Output option, the solver will look for a modelname.fmt file for instructions on which variables to integrate and on which boundary conditions they should be integrated over. See Appendix A for more information on the format of this file.
Control Panel
Output-Printed Output-Diagnostics
Diagnostics provides information about the performance of the solver. When you activate
Diagnostics, you will be prompted to select the basic or advanced level of output. The basic level instructs the solver to write information to the output file on the performance of the linear equation solvers. By default, this information will be written every iteration but you can enter an Iteration Frequency greater than 1 to reduce the amount of output generated. The advanced level contains everything in the basic level and adds trace information to the output file so that the solver subroutine entry and exit points can be monitored.
The basic level of diagnostics allows you to monitor the performance of the linear equation solvers. The advanced level is not very useful on its own and should only be activated at the request of the ESI CFD Technical Support Staff.
Diagnostic Output Control Panel
Output-Printed Output-Residual Frequency
For transient problems, you can reduce the amount of residual output by entering a residual frequency greater than 1. A value of 2 will cause the residuals to be printed every other time step resulting in one-half of the default amount of output.
Residual Frequency Control Panel
Output-Printed Output-Summary Reports
Some of the modules have the capability to produce a summary report for certain data. These summaries are usually integrations of some parameter over each valid boundary condition, as well as a summation of all of the data for the whole model. The table below contains the available printed summary reports and the modules that control them. See the referenced Module for more details.
Printed Summary Reports
Summary Report Controlling Module
Mass Flow Summary Flow
Pressure and Viscous Force
Summary Flow
Heat Transfer Summary Heat Transfer
Species Summary Chemistry
Scalar Flux Summary User Scalar
Reaction Force Summary Stress Control Panel
Output-Graphical Output
The Graphic tab enables you to choose the variables you want to save to the results file (modelname.DTF). All of these variables will be interpolated to the computational nodes and be available for post-processing with CFD-VIEW. The number of variables is too large to list here.
See each module’s section for details on what variables are available when that module has been activated.
Control Panel
Output-Monitor Points
The Monitor Point panel enables you to monitor one or more variables at one or more locations in the computational model. The Monitor Point feature will report the value of any variable at the center of the cell which contains the monitor point’s specified xyz location. The last column input is for moving mesh computations. In these cases, the monitor point can be fixed to it's nearest cell center and the monitor will move as the mesh moves. To fix a monitor point to a cell, the value should be set to 1 in the Fixed Cell column. The coordinates are in the units of the model (as of version 2008.0).
The Monitor Point output can be graphically plotted using the CFD-ACE+ built-in Monitor Point plotter (see Control Panel-Run-Plot Monitor Points). For steady-state simulations the variable value will be plotted versus iteration and for transient simulations the variables will be plotted versus time.
There are two ways to define the Monitor Point locations and variables: user input (through the CFD-ACE+) and file input (see Appendix A-Monitor Point File). There is no limit to the number of points that you can have. If the variable that you want is not in the list, then use the user input option to manually define the monitor point locations and variables.
Monitor Points Window