Solves a partial differential equation. You must manually select the polymorphic instance to use.


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Inputs/Outputs

  • cNI__PDE_lvlib_NI__PDElvclass.png PDE in —

    PDE in is the class that stores the data of the equation.

  • cerrcodeclst.png error in (no error) —

    error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

  • iNI__PDE_lvlib_NI__PDElvclass.png PDE out —

    PDE out returns PDE in unchanged.

  • i3ddbl.png U(t, x, y) —

    U(t, x, y) returns the calculated solution of the equation.

    The size of the right-sided function is # of t-points-by-# of y-points-by-# of x-points from the Define PDE Domain VI. Each page of U(t, x, y) stores the solution at mesh grid points (X, Y) from the Define PDE Domain VI at a particular time step. On one page of U(t, x, y), each row or column stores the solution on a particular y- or x-point, respectively.

  • ierrcodeclst.png error out —

    error out contains error information. This output provides standard error out functionality.

    • Before you use the PDE Solver VI, use the Define PDE, Define PDE Domain, and Define PDE Boundary Condition VIs to define the equation, domain, and boundary conditions. For an evolutionary equation, such as the heat or wave equations, use the Define PDE Initial Condition VI to define the initial condition. For each VI, select the appropriate polymorphic instance according to the type of equation you need to solve. The following block diagram illustrates how to define and solve a one-dimensional wave equation.

    For a one-dimensional problem, LabVIEW solves the equation on evenly spaced points with the finite difference method. For a two-dimensional problem defined on the rectangular domain, LabVIEW solves the equation on a uniform mesh grid with the finite difference method. For a two-dimensional problem defined on the polygonal domain, LabVIEW solves the equation on specified grid points with the finite element method. In this case, the grid points are not required to be a uniform mesh.

    Examples

    Refer to the following example files included with LabVIEW.

    • labview\examples\Mathematics\Differential Equations - PDE\PDE Flexible Element.vi
    • labview\examples\Mathematics\Differential Equations - PDE\PDE String Vibration.vi
    • labview\examples\Mathematics\Differential Equations - PDE\PDE Thermal Distribution.vi