NON-STANDARD MODEL OF TWO-DIMENSIONAL SIMPLEX T7
The paper considers the triangle T7, which has seven nodes (three nodes in the points, three nodes in the middle of the sides and one node in the barycenter). It is shown that T7, as well as standard T10 can fulfill a dual role: both of a computational pattern and a finite element. Violation of inter-element continuity (incompatibility) at the boundary with triangular T6 or square Q8 has no undesirable effects. T7 model successfully withstands lump testing. Upon that the "blown" mode of T7 opens the possibility to generate by condensation many alternative models of T6 with different integral characteristics.
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