Table of Contents
Linear elastostatics
Computational diagram
Computational steps
1. Process the mesh
The input data is written into the name.i1 text file.
All element types can be used with the exception of the sandwich and thermal contact resistance which are designed for heat transfer computations only.
| Program | RMD2 (2D problem) / RMD3 (3D problem) |
|---|---|
| Inputs | name.i1, alternatively name.NOD and name.ELE |
| Report | name.o1 |
| Outputs | binary files |
| Details | Computation overview, Mesh / Reference Manual: Inputs, Element Library, Input Syntax |
2. Process the material properties and boundary conditions
The input data is written into the name.i2 text file.
If a temperature or displacement field is available from a previous computation, it can be loaded directly from the name.TEM or name.SOL binary files, respectively.
| Program | RPD2 (2D problem) / RPD3 (3D problem) |
|---|---|
| Inputs | name.i2, binary files from the previous step, name.TEM (optionally), name.SOL (optionally) |
| Report | name.o2 |
| Outputs | binary files |
| Details | Computation overview, Material properties, Support, Loading / Reference Manual: Inputs, Quantities, Input Syntax |
3. Calculate the stiffness matrices and right-hand sides
The input data is written into the name.i3 text file.
Usually, only the restart key $\mathtt{KREST}=1$ is specified, which means the assembly of the stiffness matrices $\mathbf{K}$ of elements and the right-hand side vectors for the load cases processed in the previous step.
It is recommended to check the sums of forces and moments in the name.o3 file.
| Program | SRH2 (2D problem) / SRH3 (3D problem) |
|---|---|
| Inputs | name.i3, binary files from the previous steps |
| Report | name.o3 |
| Outputs | binary files |
| Details | Computation overview / Reference Manual: Inputs |
4. Solve the equation system
The input data is written into the name.i4 text file.
Usually, only the restart key $\mathtt{KREST}=1$ is specified, which means the assembly and factorization of the global stiffness matrix and substitution for the right-hand side vectors processed in the previous steps.
If the program is terminated prematurely due to a zero or negative pivot, it means that rigid body motion was allowed by incorrectly specified boundary conditions.
| Program | FEFS (2D / 3D problem) |
|---|---|
| Inputs | name.i4, binary files from the previous steps |
| Report | name.o4 |
| Outputs | binary files (the solution is in the name.SOL file) |
| Details | Computation overview / Reference Manual: Inputs |
5. Calculate the strains and stresses
The input data is written into the name.i5 text file, where the problem type key $\mathtt{KPROB}=0$.
It is recommended to check the equilibrium of the forces and reactions in the name.o5 file which represents the criterion for the accuracy of the solution.
| Program | STR2 (2D problem) / STR3 (3D problem) |
|---|---|
| Inputs | name.i5, binary files from the previous steps |
| Report | name.o5 |
| Outputs | name.STR (optionally), name.STB (optionally) |
| Details | Computation overview / Reference Manual: Inputs |