The issue is that 1D structural elements do not seem to be constructed properly when they not aligned with the x-axis. For example, the 1D bar extension example works fine when it is oriented along the x-axis with force acting in x-direction, but if I try to solve the same problem with the bar oriented along the y-axis instead with force acting in y-direction, it no longer solves.
I've attached a simple source file that demonstrates this.
I came about this issue when trying to solve the 10 bar truss problem, imported into MAST from an input file. In that case, I narrowed it down to the weighted Jacobian, from get_JxW(), is becoming NaN in some cases which results in NaNs in the residual and the program terminates, with a zero solution and no error code. I tried input files for the 3 bar truss and a vertically oriented 1 bar extension case, and saw the same behavior.
I tried an unmodified (i.e. from GitHub) version of MAST with the example file (attached) to rule out an issue with my input file reader or my modified MAST code. I didn't examine the weighted Jacobian for the example attached (I didn't modify the MAST source to print out this value), but I suspect the same issue is occurring here.
Although untested, I feel like this issue could spill over into other structural models with 2D and 3D elements, that utilize 1D elements as well.
bar_extension_vertical_pointload.zip
Edit 1: Fixed typo
The issue is that 1D structural elements do not seem to be constructed properly when they not aligned with the x-axis. For example, the 1D bar extension example works fine when it is oriented along the x-axis with force acting in x-direction, but if I try to solve the same problem with the bar oriented along the y-axis instead with force acting in y-direction, it no longer solves.
I've attached a simple source file that demonstrates this.
I came about this issue when trying to solve the 10 bar truss problem, imported into MAST from an input file. In that case, I narrowed it down to the weighted Jacobian, from get_JxW(), is becoming NaN in some cases which results in NaNs in the residual and the program terminates, with a zero solution and no error code. I tried input files for the 3 bar truss and a vertically oriented 1 bar extension case, and saw the same behavior.
I tried an unmodified (i.e. from GitHub) version of MAST with the example file (attached) to rule out an issue with my input file reader or my modified MAST code. I didn't examine the weighted Jacobian for the example attached (I didn't modify the MAST source to print out this value), but I suspect the same issue is occurring here.
Although untested, I feel like this issue could spill over into other structural models with 2D and 3D elements, that utilize 1D elements as well.
bar_extension_vertical_pointload.zip
Edit 1: Fixed typo