1. Reference problem#
1.1. Geometry#

Figure 1.1-a : element orientation.
The pipes are oriented in space as shown in the Figure:
Global coordinates of points \(P0\), \(\mathit{P1}\), and \(\mathit{P2}\):
\(P0=(0.0;0.0;0.0)\)
\(P1=(2\sqrt{3};0.0;0.0)\)
\(P2=(2.0;2.0;2.0)\)