PFEM Analysis

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  • PFEM2D discretize Rectangle $startNodeTag $X1 $Y1 $hx $hy $angle $Nx $Ny $Ndf <-fix $fixList -mass $massList -vel $velList -boundary $boundaryList>
    • Discretizes a rectangular area in to nodes for subsequent triangulation and PFEM analysis
    • startNodeTag -- tag of the first node that is created
    • X1 Y1 -- global X and Y coordinates of the lower left corner of the rectangle
    • hx hy -- division length in the local x and y directions of the rectangle
    • angle -- angle of rotation between the local x axis of the rectangle and the global X axis
    • Nx Ny -- number of divisions in the local x and y directions of the rectangle
    • Ndf -- number of degrees of freedom for each node that is created
    • fixList -- list of fixity values applied to all nodes that are created (1 = fixed, 0 = free, default = "0 0")
    • massList -- list of mass values applied to all nodes that are created (default = "0 0")
    • velList -- list of initial velocity applied to all nodes that are created (default = "0 0")
    • boundaryList -- list of codes for including boundary nodes on the sides of the rectangle (1 = include, 0 = omit, default = "1 1 1 1")
    • The return value from this command is the tag of the last node created


  • PFEM2D fluid $nodeList <-append>
    • Assigns nodes to be fluid nodes
    • nodeList -- list containing the start and end nodes for assignment
    • -append -- appends the nodes to the current set of fluid nodes (default = overwrites the current set)


  • PFEM2D structure $nodeList <-append>
    • Assigns nodes to be structure nodes
    • nodeList -- list containing the start and end nodes for assignment
    • -append -- appends the nodes to the current set of structure nodes (default = overwrites the current set)


  • element PFEMElement2D $tag $ndI $ndJ $ndK $rho $mu $bX $bY <$thickness>
    • Creates a triangular fluid element for 2D PFEM analysis
    • tag -- idenifying element tag
    • ndI ndJ ndK -- connected element nodes (should be defined in counter-clockwise order around the element)
    • rho -- fluid density
    • mu -- fluid viscosity
    • bX bY -- body forces in the global X and Y directions
    • thickness -- out of plane element thickness (default = 1.0)


  • PFEM2D doTriangulation $alpha -nodes $nodeList -PFEMElement2D "$startEleTag $rho $mu $bX $bY <$thickness>"
    • Triangulates the given nodes in to a mesh of fluid elements for 2D PFEM analysis
    • alpha -- alpha-shape parameter for identifying boundaries (usually between 1.4 and 1.5)
    • $nodeList -- list containing the start and end node tags for triangulation
    • $startEleTag -- tag of the first element that is created
    • $rho $mu $bX $bY <$thickness> -- see PFEMElement2D command
    • The return value from this command is the tag of the last element created


  • analysis PFEM $dtmax $dtmin
    • Creates a PFEM analysis object
    • dtmax dtmin -- the maximum and minimum time steps to be used during the analysis


More commands will be documented soon


Code maintained by: Michael H. Scott, Oregon State University