CELAS4

Bulk Data Entry Defines a scalar spring element that is connected only to scalar points without reference to a property entry.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CELAS4 EID K S1 S2 GE S

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
CELAS4 42 6.2-3 2

Definitions

Field Contents SI Unit Example
EID Unique element identification number.

No default (Integer > 0)
K Stiffness of the scalar spring.

No default (Real)
S1, S2 Scalar point identification numbers.

S1 or S2, but not both, may be blank or zero indicating a constrained coordinate.

Default = 0 (Integer ≥ 0; S1 ≠ S2)
GE Damping coefficient.

GE is ignored in transient analysis, if PARAM, W4 is not specified.

Default = 0.0 (Real)
S Stress coefficient.

Default = 0.0 (Real)

Comments

  1. This single entry completely defines the element since no material or geometric properties are required.
  2. Only one scalar spring element may be defined on a single entry.
  3. A scalar point specified on this entry does not need to be defined on a SPOINT Bulk Data Entry.

  4. The element force of a spring is calculated from the equation:

    f = k * ( u 1 − u 2 ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamOzaiabg2 da9iaadUgacaGGQaWaaeWaaeaacaWG1bWaaSbaaSqaaiaaigdaaeqa aOGaeyOeI0IaamyDamaaBaaaleaacaaIYaaabeaaaOGaayjkaiaawM caaaaa@3FD2@
    Where, k MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4uaaaa@36CE@ is the stiffness coefficient for the scalar element, u 1 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyDamaaBa aaleaacaaIXaaabeaaaaa@37D7@ is the displacement of the first degree-of-freedom listed on the CELAS1 and CELAS2 entries and u 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamyDamaaBa aaleaacaaIXaaabeaaaaa@37D7@ is the displacement of the second degree-of-freedom listed on the CELAS1 and CELAS2 entries.

    Element stresses are calculated from the equation:

    s = S * f MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4Caiabg2 da9iaadofacaGGQaGaamOzaaaa@3A65@
    Where, S MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaam4uaaaa@36CE@ is the stress coefficient as defined above.

  5. This card is represented as a spring or mass element in HyperMesh.