Python wrapper for FEM1D program from J.N. Reddy. Use this to generate the problem data cards or alternatively solve straight from python.
Initialize an FEM1DProblemData object with the list nodes_per_element pass the problem data as a dictionary to **kwargs.
nodes_per_element = [2, 3, 2, 2]
problem_data = {...} # dictionary
fea_mesh = FEM1DProblemData(nodes_per_element, **problem_data)
fea_mesh.save_card('example.inp') # to produce the data card file
solution = fea_mesh.run() # to run the problem and get the output card as a string
See data_format.md for how to format the problem data dictionary. Variables follow same names as given in the FEM1D Input Description. Some data is generated automatically when the information is redundant.
For Euler-Bernoulli beam steady-state deflection problems, EulerBernoulliBeam implements FEM1DProblemData with a higher level interface. Pass a, b, c, and f as functions, and as long as they are piecewise linear breaking at node points, the code will calculate the problem data. Add boundary constraints or other DOF constraints with the method specify_dof(x, loc, var_type).
def f(x): # example loading
if(x >=0 and x <= 1):
return 8000 - 8000*x
if(x>= 2 and x<= 4):
return 8000
return 0
EI = 3000000
b = lambda x: EI
beam = EulerBernoulliBeam(6, 6, f=f, b=b, title='Euler Bernoulli Beam, 6 elements')
beam.specify_dof(0, 0, 'w') # deflection left boundary condition
beam.specify_dof(0, 0, 'm') # moment left boundary condition
beam.specify_dof(0, 2, 'w')
beam.specify_dof(0, 4, 'w')
beam.specify_dof(0, 6, 'w') # deflection right boundary condition
beam.specify_dof(-2000, 6, 'm') # moment right boundary condition
beam.run()
I couldn't verify the license for FEM1D by J.N. Reddy, although the program is freely available on the McGraw Hill website. Before running the code, download the .exe and place it in /fem1d.