13.272. SOLID272 - General Axisymmetric Solid with 4 Base Nodes

Matrix or Vector	Geometry	Shape Functions	Integration Points*
Stiffness and Stress Stiffness Matrices; and Thermal Load Vector	Quad	Equation 11–263, Equation 11–264, Equation 11–266, Equation 11–267, and Equation 11–268	2 x 2 x N_c
	Triangle	Equation 11–263, Equation 11–264, Equation 11–269, Equation 11–270, and Equation 11–271	1 x N_c
Mass Matrix	Quad	Same as stiffness matrix	2 x 2 x N_c
Mass Matrix	Triangle	Same as stiffness matrix	1 x N_c
Pressure Load Vector	Same as stiffness matrix, specialized to face		2 x N_c

* N_c = the number of integration points in the circumferential direction. The N_c integration points are circumferentially located at:
the nodal planes, and
midway between the nodal planes (that is, at the integration planes)
so that N_c = (2 * N_np), where N_np = number of nodal planes (KEYOPT(2)). Exception: If KEYOPT(2) = 1, then N_c = 1.

Load Type	Distribution
Element Temperature	Bilinear across element on rz plane, linear in circumferential direction
Nodal Temperature	Same as element temperature distribution
Pressure	Linear along each face

13.272.1. Other Applicable Sections

Structures describes the derivation of structural element matrices and load vectors as well as stress evaluations.

13.272.2. Assumptions and Restrictions

Although the elements are initially axisymmetric, the loads and deformation can be general in nonaxisymmetric 3-D. The displacements are interpolated in elemental coordinate system by interpolation functions, but the user can define the nodal displacements in any direction.