Raw PVT Data dialog
This dialog allows you to input measured pressure, specific volume, and temperature (PVT) data, or use a generic PVT model.
Generic PVT Data (Thermoplastics only)
If you select this option, estimated supplemental data values associated with the Family Abbreviation and Filler information that you specified in the General Information and Filler dialogs will be used.
Input raw data
Selecting this option allows you to enter measured PVT data for this material.
Tabulated PVT Data
The raw PVT data consists of temperature, pressure and specific volume values. These data can be input or edited cell-by-cell in the table, or as space-delimited data (typically copied and pasted from a spreadsheet) by clicking Go to Text Editor.
In order for the 2-Domain Tait PVT Model to be fit, the following minimum requirements must be met:
- At least two different pressures must be included
- At least three temperatures must be below the Ttrans for at least two pressures
- At least three temperatures must be above the Ttrans for at least two pressures
Violating these requirements will result in an error message popup.
If there is a problem meeting the minimum required data, please contact Autodesk Moldflow Data Fitting at datafittingmoldflow@autodesk.com.
More data is recommended to achieve a better model fit.
Plot
Click the Plot button at the top of the dialog to visualise the tabulated input data.
Click the Toolbar plot button to return from the plot.
PVT Transitions
If the material structure is amorphous according to the family selected in the General Information dialog or a thermoset, these inputs do not apply and will be disabled.
If the material is crystalline, the user must choose a transition of the material at a low pressure and a transition at a high pressure. These two points assist in generating the b5 and b6 parameters in the 2-Domain Tait PVT Model.
The point selection can be estimated by plotting the raw data and finding two transitions: Low Pressure and High Pressure.
Each transition point consists of an extrapolated line between the solid state and the melt state of the material at low and high pressure where the change of state is judged as a rate of change of pressure. The temperature is estimated at the transition.
The exact values of the b5 and b6 parameters can then be tweaked, numerically or graphically, in the PVT Model dialog.
PVT Data Test information
This section of the dialog contains information about the material test such as source, method and date of creation.