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ForceToStress.f90
ForceToStress
Stress
(user defined) Force
For a given boundary, this solver computes the nodal stress equivalent to a given nodal force. Force here means the resultant of a variable, named stress, which is of the same units than the force but per m2 in 3D or m in 2D. This can be used also to infer the flux from the knowledge of a debit or to infer a tangential stress from the knowledge of a tangential force.
In the SIF example below, the normal stress on a boundary is inferred from the 3rd component of the Stokes residual.
Solver 1 Equation = "Navier-Stokes" Stabilization Method = String Stabilized Flow Model = Stokes ... Exported Variable 1 = Flow Solution Loads[Fx:1 Fy:1 Fz:1 CEQ Residual:1 ] Calculate Loads = Logical True End Solver 2 Equation = "ForceToStress" Procedure = File "ElmerIceSolvers" "ForceToStress" Variable = String "Stress" Variable DOFs = 1 Force Variable Name = String "Fz" Linear System Solver = Direct Linear System Direct Method = umfpack End ! Solve this for body Id 2 (=boundary 3 here) Equation 2 Active Solvers(1) = 2 End !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Boundary Condition 3 Target Boundaries = 5 Body Id = 2 ... End
In the example found in [ELMER_TRUNK]/elmerice/examples/Test_ForceToStress
, a pressure applied on a boundary is first integrated to get nodal force using the GetHydrostaticLoad Solver, and then the pressure is recovered using the ForceToStress
Solver.