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app_style potts/am/weld command


app_style style nspins alpha beta haz

  • style = potts/am/weld
  • nspins = number of possible Potts model spins
  • alpha = controls relative size of melt pool shape at bottom compared to top
  • beta = Bezier control point parameter that defines curvature of melt pool shape through thickness
  • haz = width of the heat affected zone (haz) surrounding the melt pool


    app_style potts/am/weld 10000 0.5 0.75 50.0
    weld_shape_ellipse 100.0 150.0 

    The app_style potts/am/weld command uses a subset of the command parameters used by app_style potts/weld -- additional explanation provided below. For an explanation of the above commands and parameters, see potts/weld example. This application requires melt pool geometry commands -- per example above and explanation below.

    This application requires rastering commands -- per explanation given below.

    The pulse command is disabled in this application.


    This is an application for 2D additive manufacturing simulations and is an adaptation of potts/weld; it can be viewed as a potts/weld model with rastering commands as defined and used by potts_additive. The 2D limitation of this app derives from the full penetration weld assumption; potts/weld; does not have a melt pool bottom that naturally occurs in an additive manufacturing build the z-direction. Thickness of the lattice in the z-direction is taken as the plate thickness per description in the potts/weld; such simulations will produce meaningful 3D microstructures. However, it is generally more efficient to run 2D calculations with this app using only one plane of lattice sites.

    Application potts/am/weld command values are all associated with potts/weld and have identical interpretations/meanings for potts/am/weld. Some values, e.g. yp,velocity, used in potts/weld, have been moved to raster commands.

    The following commands must be used to specify pool geometry:

    weld_shape_ellipse specify elliptical pool shape parameters
    weld_shape_teardrop specify teardrop pool shape parameters

    The following additional commands are typically used by this application. A layer must be defined: one of am cartesian_layer or am path_layer. A layer requires 1 to many am path or at least 1 am pass. Since this application only runs 1 layer, the am build command described below is optional.

    am pass: Specify pass parameters used to construct cartesian_layer.

    am path: Specify arbitrary paths via start/end points on a layer; sequence of am paths are used to construct an am path_layer.

    am cartesian_layer: A scan pattern on rectangular layer constructed from am pass and other parameters.

    am build: May be used to combinations of layers that comprise a pattern.

    NOTE: Because potts/am/weld is intended for 2D simulations, only the first layer, as specified in the am build command, is used; this application does not simulate multilayer builds. The examples/potts_additive directory has input files which illustrate how to use the rastering commands.

    The temperature command should be used to set simulation Monte Carlo temperature.


    This application is only compatible with square and square cubic lattices. It can only be evolved by a rejection KMC (rKMC) algorithm. See sweep for more information.

    Additional related commands:

    app_style potts, app_style potts/grad, app_style am/ellipsoid, app_style potts/weld

    Default: none