Hello,
I have a question regarding *CLOAD card. I need to manually include forces in C3D10 element nodes correctly.
In writer.py script, one can find the following code, which is the responsible for writing the forces of *CLOAD card.
def write_constraints_force(self, f):
# check shape type of reference shape and get node loads
self.get_constraints_force_nodeloads()
# write node loads to file
f.write('\n***********************************************************\n')
f.write('** Node loads Constraints\n')
f.write('** written by {} function\n'.format(sys._getframe().f_code.co_name))
f.write('*CLOAD\n')
for femobj in self.force_objects: # femobj --> dict, FreeCAD document object is femobj['Object']
f.write('** ' + femobj['Object'].Label + '\n')
direction_vec = femobj['Object'].DirectionVector
for ref_shape in femobj['NodeLoadTable']:
f.write('** ' + ref_shape[0] + '\n')
for n in sorted(ref_shape[1]):
node_load = ref_shape[1][n]
if (direction_vec.x != 0.0):
v1 = "{:.13E}".format(direction_vec.x * node_load) # Help! Need to find node_load values
f.write(str(n) + ',1,' + v1 + '\n')
if (direction_vec.y != 0.0):
v2 = "{:.13E}".format(direction_vec.y * node_load) # Help! Need to find node_load values
f.write(str(n) + ',2,' + v2 + '\n')
if (direction_vec.z != 0.0):
v3 = "{:.13E}".format(direction_vec.z * node_load) # Help! Need to find node_load values
f.write(str(n) + ',3,' + v3 + '\n')
f.write('\n')
f.write('\n')
I understand this code. The result is basically a sorted list of 3 components: node number, direction (1=x,y=2,z=3), force magnitude in the node
e.g.
22,3,1000.000000000000 # the node 22 has a force of 1000 [N] in z direction.
23,3,500.000000000000 # the node 23 has a force of 500 [N] in z direction.
...
In order to include forces correctly in C3D10 element nodes, I need to define correctly the aforementioned 3 components.
1.- The definition of a manually selected nodes is not a handicap, it is discussed here: https://forum.freecadweb.org/viewtopic.php?f=18&t=31123&start=10#p258488
2.- The definition of the direction is not a handicap. x=1,y=2,z=3
3.- My problem is here in the third component: the magnitude of the force for each node.
The last part has a product of two variables: direction_vec.x * node_load direction_vec is not a handicap. The definition of Node_load is my real problem
In order to include forces correctly in C3D10 element nodes, I need to find in FreeCAD folder the python or C++ scripts where the following four functions are defined:
1.- self.get_constraints_force_nodeloads()
2.- self.force_objects
3.- femobj[‘NodeLoadTable’]
4.- node_load = ref_shape[1][n]
I guess that all of them should be in the same script… but I dont know where are defined.
I arrived until here: def FemInputWriter.FemInputWriter.get_constraints_force_nodeloads(self ) but I dont find the python or C++ script.
best regards,
Ekaitz.
More info regarding C3D10 element here: [url][http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node33.html[url](http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node33.html[url)]
