CQAXIG

Bulk Data Entry Defines a quadrilateral cross-section general axisymmetric element that allows circumferential deformation.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CQAXIG EID PID Theta
G1 G2 G3 G4 G5 G6 G7 G8

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CQAXIG 111 2 15.0
31 74 75 32 51 52 63 62

Definitions

Field Contents SI Unit Example
EID Unique element identification number.

No default (Integer > 0)

PID A PAXIG entry identification number.

Default = EID (Integer > 0)

G1, G2, G3, G4 Identification numbers of corner grid points.

No default (Integers > 0, all unique)

G5, G6, G7, G8 Identification numbers to edge grid points.

No default (Integers > 0 or blank)

Theta Material orientation angle in degrees.

Default = 0.0 (Real)

Comments

  1. Element identification numbers must be unique with respect to all other element identification numbers.
  2. The property card entry to reference is PAXIG, which assigns the material and the axis-of-symmetry to the element.
  3. In comparison with 2d axisymmetric elements CQAXI and CTAXI (which have two degrees of freedom at each node), general axisymmetric elements have an additional degree of freedom at each node circumferentially; they can also have torsional deformation about the axis-of-symmetry.
  4. The grid ordering of G1 through G8 is defined as shown in Figure 1. All grids and the axis-of-symmetry must be on the same plane, and the grids cannot span across the axis-of-symmetry on this plane.
    Figure 1. CQAXIG Definition


  5. If the PAXIG entry referenced in field 3 references a MAT3 entry, material properties and stresses are always given in the xm-zm coordinate system.
  6. A concentrated load (as in, the load specified on a FORCE entry) at a grid Gi of this element denotes that force applied onto the circumference with radius of Gi. For example, to apply a load of 200 N/m on the circumference at Gi located at a radius of 0.4 m, the magnitude of the load specified on the static load entry is:
    200N/m ** 0.4m =502.655N MathType@MTEF@5@5@+= feaahqart1ev3aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaebbnrfifHhDYfgasaacH8srps0l bbf9q8WrFfeuY=Hhbbf9v8qqaqFr0xc9pk0xbba9q8WqFfea0=yr0R Yxir=Jbba9q8aq0=yq=He9q8qqQ8frFve9Fve9Ff0dmeaabaqaciGa caGaaeqabaqaceaadaaakeaadaqadaqaaiaajkdacaqIWaGaaKimai aaj6eacaqIVaGaaKyBaaGaayjkaiaawMcaaiaaykW7caqIQaGaaGPa VlaajkdacaqIapGaaGPaVlaajQcacaaMc8+aaeWaaeaacaqIWaGaaK OlaiaajsdacaqITbaacaGLOaGaayzkaaGaaGPaVlaaj2dacaaMc8Ua aKynaiaajcdacaqIYaGaaKOlaiaajAdacaqI1aGaaKynaiaaj6eaaa a@503E@
  7. General axisymmetric elements are supported in linear analyses (including static and dynamic analyses) and linear static preloading subcases.
  8. PARAM,AXI2DTOR,YES can be used to convert 2D axisymmetric elements CQAXI and CTAXI in the model to general axisymmetric elements CQAXIG and CTAXIG, respectively, while PAXI is considered as PAXIG.