The System Coupling Service log file (scLog.scl) provides key run time information and is divided into four blocks:
• start-up and executable information,
• coupled analysis setup information,
• solution details,
• and shut-down information.
The start time and date, command line information and executable details for the run appear as follows:
Run start time and date: 10:15:41, Sep 19 2014 Command line used to start this service:
C:\Program Files\ANSYS Inc\v160\aisol\bin\winx64\Ansys.Services.SystemCoupling.exe -inputFile scInput.sci
======================================================================
The command used to start the System Coupling service is given next as shown below:
Command line used to start this service: C:\Program Files\ANSYS Inc (Dev)\v160\aisol\bin\winx64\Ansys.Services.SystemCoupling.exe
An echo of the SC service input file is provided next in the log file below the following header:
======================================================================
The information generally found in this section includes unit system data (for example, MKS, and so on), as well as information relating to coupling (time versus coupling step), initialization (options such as time value or initial coupling step), duration (for example, end time), and step size and the maxim-um/minimum number of iterations.
Note
When the coupling is defined by coupling step (and not by time), then time-related inform-ation (initial time, end time, or step size) is not displayed in this section of the log file, and only step-related information is available (for example, initial step, number of steps, maximum and minimum iterations).
Summary of System Coupling Setup
Under this section of the log file, there are sub-blocks (for example, “Analysis Information”, “Coupling Participant Information”, “Data Transfer Information”, “Execution Control Information”, “Setup Validation“
and “System Coupling Co-Simulation Summary”). A brief description of these sub-blocks is provided below.
Understanding the System Coupling Log File
The Analysis Information section includes basic information about the coupling definition, the unit system, as well as time and step information.
======================================================================
The Coupling Participant Information section includes information about each of the solvers connected to the system coupling simulations (for example, internal name, type (either Co-Simulation or Static Data), units, and so on). Additional information for coupled regions and variables that appear in data transfers is also displayed in this section of the log file. This additional information includes: the coupled name and type (for regions); and the variable name and physical type (for variables). This information is not displayed for regions and/or variables that do not participate in data transfers. If such regions or variables exist, a message is written to indicate that the related information has been omitted from this section of the log file.
+---+
Summary of Coupling Regions (1)
Region : File1 Internal Name = ExtDataReg_Setup 2_0 Type = Surface Summary of Coupling Variables (1)
Variable : Temperature1 Internal Name = ExtDataVar_Setup 2_0_1 Physical Type = Temperature Summary above omits variables not used in data transfers.
Summary of Base Units (9)
Angle = radian
The Data Transfer Information section includes:
• Region and variable information for the source and target of each data transfer
• Data transfer options, such as the convergence criteria and target
• The under-relaxation factor
Understanding the System Coupling Log File
Source : Fluent
The Execution Control Information section includes a summary of the sequencing of co-simulation participants, and requests for debug and intermediate result file output. Note that the debug and inter-mediate result output summaries are generated only if such output is requested. For example:
======================================================================
The Setup Validation section includes any warning or error messages that may have been generated.
For example:
======================================================================
1 ) Auto-Correction: The specified maximum iterations per step is less than the specified minimum iterations. The maximum iterations will be set to the minimum iterations.
+---+
| Errors ( 1) | +---+
1 ) The solution sequence specified for the participant named 'Fluent' is not greater than zero. Adjust this (and other) sequence values appropriately.
The System Coupling CoSimulation Summary section includes a brief summary of the participants in the co-simulation.
Next is the “Solution” block. Under it, the following information is provided.
======================================================================
The Solution block contains a Mapping Summary section:
+---+
The current coupling step number and the current simulation time are reported as shown below. This information will be a part of a box that is repeated in the log file at the beginning of every coupling step. It looks similar to the following:
+====================================================================+
| COUPLING STEP = 1 SIMULATION TIME = 0.001 |
|---|
| Solver | Solution Status |
Understanding the System Coupling Log File
| Data Transfer | |
| Diagnostics | Source Side Target Side | +====================================================================+
Note that if the simulation is defined only by steps (and not by time), then the log file output will only present step-related information.
Next is another box that repeats every coupling iteration of every coupling step. It looks like:
+---+
As indicated above, after every coupling iteration, the convergence status is given for each participant.
Common participant status values are Converged and Not yet converged..., however, Diver-gence detected... and Status Unavailable could also be reported. Below the solver status is a list of the data transfers for which the participant is the target, plus diagnostics used to evaluate convergence of the data transfer. Any supplemental diagnostics (as described in the SC Log Output Control Settings section in Understanding the System Coupling Input File (p. 58)) that have been re-quested are also included here.
Notes specific to the execution of a given coupling step will be reported under the final coupling iteration of the step. For example:
Next is the “Shut Down” block under which the following information is included:
======================================================================
System Coupling Service shut down...
Run completed successfully.
The preceding output is generated under normal shutdown conditions. If a co-simulation participant (or the coupling service itself ) fails during the analysis, the normal shutdown output will be replaced by messages similar to the following:
+====================================================================+
| NOTICE | | An exception has occurred and has been transmitted to the coupling | | participants. These participants have been disconnected from the | | coupling service. | +====================================================================+
+====================================================================+
| System Coupling Exception | +====================================================================+
| Origin : Fluids Problem (Solution 1) | | Error Code : 2 | | Error Description : | | Fluent encountered fatal error after sync point Solve | +====================================================================+
System coupling run completed with errors.
The first block indicates that all co-simulation participants have been notified of the problem. The second block indicates the origin (that is, the coupling participant) of the failure, and an error code and description. For additional information, see Troubleshooting Two-Way Coupled Analyses Problems (p. 73).
Understanding the System Coupling Log File