Data Files

All simulators utilize a text-based file as the source of input data. This file can be edited within the Operating Parameter panel of the user interface, or with any text editor, and saved with a .par extension. A template of a data file can be generated by selecting the Create Data Template button in the Operating Parameter panel and selecting the desired units and process characteristics. The resulting data file will be based on melting Alloy 718 in a commonly used melt configuration. Data files are not associated with any particular alloy or slag property file and so can be used in multiple melt scenarios, however the melt profile parameters might have to be altered so as to be appropriate for the new melt scenario. The data file also gives the user the opportunity to select the desired system of units for temperature, length, melt rate, etc.

Operating Parameters

One distinguishing feature of these simulators is that they all combine a model of the heat source with electrode and ingot models.

This means that input data are expressed in terms of parameters that the operator controls – voltage, melt rate or current, arc gap or swing depth, etc. rather than having to “translate” these parameters into a temperature or heat flux boundary condition at the top of the ingot.

Result Files

Result files are created in a variety of formats depending on the selected output parameters. Due to the potential large number of result files, the user is given control over which results to generate, and which file format to produce. A text-based file with an appropriate extension (*.esr, *.slb, *.var) is always created and contains a summary of the input data, a summary of the melt results, and results for all selected output parameters. Additional text based files are also created for use in plotting melt profiles (operating parameters, solidification conditions, LST) within ParaView. An option to generate comma-separated value (CSV) files for appropriate output parameters is available to permit further detailed analysis in Excel. Similarly, Visual Toolkit (VTK) files can be generated to permit visualization of 2-D results in ParaView, which can be done expeditiously upon completion of a simulation.

Boundary Conditions

The specification of boundary conditions presents one of the more significant challenges in developing a remelt simulator. Based on comparisons between model results and data presented in the literature, a set of boundary conditions for each case has been determined and can be invoked by specifying the parameter as ‘-1’ in the input data file. Each of these parameters can be overwritten by the user if so desired.

Execution

Execution times are quite fast, generally being in the range of 1-2 minutes.

Accuracy

The accuracy of model results is generally in the order of 5-10% based on comparisons between predicted and measured pool profiles. The one exception is the case of VAR melting at high melt currents where significant fluid flow occurs in the pool. However these conditions are generally not encountered in a successful melt practice for segregation-prone Ni-Co-Fe superalloys.

Video Support

The video support page includes a series of short instructional videos to assist in familiarization of the models and their execution.