How many 3d element shapes are there in ansys software?
Answers
MESHING TYPES part PLANE82'. Element types are defined in the input file with ANSYS 'ET' commands. The element type number is assigned by the interface program. The same element type can be defined twice with two different numbers if its material or/and physical properties are different from one to the other.
Explanation:
A three-dimensional (3D) solid element can be considered to be the most general of all solid finite elements because all the field variables are dependent of x, y and z. As can be seen, the force vectors here can be in any arbitrary direction in space. A 3D solid can also have any arbitrary shape, material properties and boundary conditions in space. As such, there are altogether six possible stress components, three normal and three shear, that need to be taken into consideration. Typically, a 3D solid element can be a tetrahedron or hexahedron in shape with either flat or curved surfaces. Each node of the element will have three translational degrees of freedom. The element can thus deform in all three directions in space.Since the 3D element is said to be the most general solid element, the truss, beam, plate, 2D solid and shell elements can all be considered to be special cases of the 3D element. So, why is there a need to develop all the other elements? Why not just use the 3D element to model everything? Theoretically, yes, the 3D element can actually be used to model all kinds of structurural components, including trusses, beams, plates, shells and so on. However, it can be very tedious in geometry creation and meshing. Furthermore, it is also most demanding on computer resources. Hence, the general rule of thumb is, that when a structure can be assumed within acceptable tolerances to be simplified into a 1D (trusses, beams and frames) or 2D (2D solids and plates) structure, always do so. The creation of a 1D or 2D FEM model is much easier and efficient. Use 3D solid elements only when we have no other choices. The formulation of 3D solids elements is straightforward, because it is basically an extension of 2D solids elements. All the techniques used in 2D solids can be utilized, except that all the variables are now functions of x, y and z. The basic concepts, procedures and formulations for 3D solid elements can also be found in many existing topics (see, e.g., Washizu, 1981; Rao, 1999; Zienkiewicz and Taylor, 2000; etc.).