For the case of a flutter analysis, your simulation will involve aerodynamic damping monitors, which should remain approximately constant as the flow simulation around the monitored surface reaches a quasi-periodic state. A consistently positive value of aerodynamic damping is an indication that blade vibration is damped (at the frequency being studied). For a description of the settings involved in setting up aerodynamic damping monitors, see Aerodynamic Damping in the CFX-Pre User's Guide.
The CFX-Solver Output file contains, for each domain, the starting and ending time steps for the data compression algorithm, as well as the fundamental period. For details, see CFX-Solver Output File (Transient Blade Row Runs) in the CFX-Solver Manager User's Guide.
CFD-Post has built-in data instancing capabilities. For details, see Data Instancing Tab in the CFD-Post User's Guide.
CFD-Post can show GPU-accelerated animations for transient blade row cases. For details, see GPU Accelerated Animation in the CFD-Post User's Guide.
Note: When using the Time Transformation or Fourier Transformation pitch change model, a stationary monitor point returns incorrect values to the CFX-Solver Manager whenever it falls outside of the rotating domain. Monitor point values are calculated as a postprocessing step, so have no effect on the solution unless used as input.
The workaround is to perform the following steps in CFD-Post:
Expand the domain where the stationary point lies using the data instancing feature. For details, see Data Instancing Tab in the CFD-Post User's Guide.
Create a circumferential line that passes through the location of interest. For details, see Turbo Line Command in the CFD-Post User's Guide.
Create a chart using the circumferential line. Plot along this line the variable of interest versus Theta. It is recommended to control the abscissa's range to be bounded between 0 and 360 degrees. For details, see Chart Command in the CFD-Post User's Guide.
In many flow simulations, it may be advantageous to start the simulation with a low number of time steps per period in order to pass through the initial transient phases of the solution, then later increase the number of time steps per period to accurately capture the flow physics. For a large simulation, this strategy can help reduce the overall simulation time required to reach convergence.
You can stop a Time Transformation or Fourier Transformation simulation and then resume it with an increased number of time steps per period.
An important constraint on how you increase the number of time steps for Fourier Transformation simulations is that the number must be doubled. For example you could start with 40 time steps per period, then restart with 80, then 160.
There is no such constraint for Time Transformation simulations. For example, you could start with 40 time steps per period, then restart with 50, then 70.