Let us compute the simplest finite element simulation to demonstrate how the femCalc works. Every simulation in femCalc is defined by a script. Let us demonstrate the script on a simple example guiding you step by step.
Let us consider a cantilever with rectangle cross-section fixed on one end and loaded by pressure on the opposite end. The cantilever length in -direction is meters, the width -direction is meters and the height -direction is meters. The geometry is defined by command
BLOCK, 1, 2, 0.1, 0.2
is consider the hyperelastic Neo-Hookean with properties close to steel, defined by shear modulus and bulk modulus
MAT, 1, NEOHOOK, 80E9, 200E9
3) Boundary Conditions
Let us fix the structure on the surface 1, which is the left one of the two surfaces in direction of global -axis
DA, 1, 1, ALL, ALL
The second parameter fixes rotational dof's (degrees of freedom), whereas the first one fixes translational dof's.
Let us load the cantilever on surface 2, which is the right one of the two surfaces in direction of global -axis by negative pressure
SFA, 1, 2, -480E6
5) Element Type
The cantilever is going to be build of the linear brick BRICK24 elements.
The number of elements is in the cantilever direction, in the other directions let us set the number at .
MESH, 1, 10, 2, 2
7) Final Script
The final script looks as follows:
BLOCK, 1, 2, 0.1, 0.2 MAT, 1, NEOHOOK, 80E9, 200E9 DA, 1, 1, ALL, ALL SFA, 1, 2, -480E6 ET, BRICK24 MESH, 1, 10, 2, 2
The definition of our simulation is finished. Click on Submit to send script to calculation.
Note: Sequence of the commands in the script is irrelevant.
You get the maximal deflection of the structure: .
Simulation start *** BLOCK 0: ni = 10nj = 2nk = 2 Number of elements = 40, Number of unknowns = 270, s_opt = 41 Gauss_elimination 1. dqmax = 0,00451085367507972, DMX = ,0045114281, PRESSURE: dp = 197631711, p = -197631711 2. dqmax = 3,96044445641079E-06, DMX = ,0045153872, PRESSURE: dp = 21618, p = -197635876 3. dqmax = 6,96920886919616E-09, DMX = ,0045153941, PRESSURE: dp = 54, p = -197635916 4. dqmax = 3,23320734970113E-12, DMX = ,0045153941, PRESSURE: dp = 1, p = -197635915 Solver stopped due to: max.decay < epsilon (dp = 1) Solver has finished reaching maximal number of iterations.