# GENEL

Bulk Data Entry Defines the stiffness, flexibility, mass, viscous damping, or structural damping of a general element connected to an arbitrary number of grids.

## Format (Stiffness Matrix)

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL EID   GI1 CI1 GI2 CI2 GI3 CI3
GI4 CI4 GI5 CI5 etc.
UD   GD1 CD1 GD2 CD2 GD3 CD3
GD4 CD4 GD5 CD5 etc.
K or Z KZ11 KZ12 KZ13 etc. KZ21 KZ22 etc.
KZ31 KZ32 etc.
S S11 S12 S13 etc. S21 S22 etc.
S31 S32 etc.

## Format (Mass Matrix)

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL EID   GI1 CI1 GI2 CI2 GI3 CI3
GI4 CI4 GI5 CI5 etc.
M M11 M21 M31 etc. M22 M32 etc
M33 M43 etc.

## Format (Viscous Damping Matrix)

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL EID   GI1 CI1 GI2 CI2 GI3 CI3
GI4 CI4 GI5 CI5 etc.
B B11 B21 B31 etc. B22 B32 etc
B33 B43 etc.

## Format (Structural Damping Matrix)

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL EID   GI1 CI1 GI2 CI2 GI3 CI3
GI4 CI4 GI5 CI5 etc.
K4 K411 K421 K431 etc. K422 K432 etc
K433 K443 etc.

## Example 1

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL 537   1001 1 1001 2 1001 3
1002 1 1002 2 1002 3
K 5757. -816.6 -43.1 -5757. 816.6 43.1 35479.3
-1151. 816.6 -35479.3 1151. 6538.6 43.1 1151. -6538.6
5757. -816.6 -43.1 35479.3 -1151. 6538.6

## Example 2

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL 4001   1073 1 1073 2 1073 3
1073 4 1073 5 1073 6
UD   1074 1 1074 2 1074 3
1074 4 1074 5 1074 6
Z .592-6       .39-6   .592-6
-.39-6     .1-9
.319-6     .319-6   .1-9

## Example 3

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL 435   11 1 23 4 72 0
17 2
S 1.7 2.3 3.6 4.4 5.2 6.8 7.1
8.9
K .1 .2 .3 .4 .5 .6 .7
.8
UD   12 2 47 0

## Example 4

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
GENEL 435   11 1 23 4 72 0
17 2
M 2.1 3.2 1.8 2.2 0.9 1.2 3.1
0.89

## Definitions

Field Contents SI Unit Example
EID Unique element identification number.

No default (Integer > 0)

GIi/CIi Grid (or scalar point) and component identification numbers ordered according to stiffness or flexibility values specified after KZmn. For scalar points, CIi is zero.

No default (GIi is integer > 0 and CIi is integer > 0)

UD Flag indicating that the subsequent fields and continuation entries contain values for GDj/CDj until K, Z, or S is specified in field 2 or it is the end of the entry.

No default (Character)

GDj/CDj Grid (or scalar point) and component identification numbers ordered according to the columns in the S matrix.

No default (GDj is integer > 0 and CDj is integer ≥ 0)

K or Z Flag indicating that the next fields and continuation entries contain stiffness values until UD or S is specified in field 2 or it is the end of the entry.

No default (Character)

KZmn Stiffness or flexibility matrix for degrees-of-freedom in GIi/CIi where m is the row number and n is the column number. Only the lower triangular terms in the matrix need to be specified. Zero values must be specified as blank or 0.0.

Default = 0.0 (Real)

S Flag indicating that the subsequent fields and continuation entries contain values for the S matrix.

No default (Character)

Sij S matrix values where I corresponds to GIi/CIi list and j corresponds to GDj/CDj list until K, Z, or UD is specified in field 2 or it is the end of the entry. All the terms in the matrix must be specified and zero values must be specified as blank or 0.0.

Default = 0.0 (Real)

Mass Matrix: 8 9 10
GIi/CIi Grid (or scalar point) and component identification numbers ordered according to mass values specified in Mmn.

No default (GIi is Integer > 0 and CIi is Integer ≥ 0)

M Flag indicating that the next fields and continuation entries contain mass values until it is the end of the entry.

No default (Character)

Mmn Mass matrix for degrees-of-freedom in GIi/CIi where “m” is the row number and “n” is the column number. Only the lower triangular terms in the matrix need to be specified. Zero values must be specified as blank or 0.0.

Default = 0.0 (Real)

Viscous Damping Matrix: 8 9 10
GIi/CIi Grid (or scalar point) and component identification numbers ordered according to viscous damping values specified in Bmn.

No default (GIi is Integer > 0 and CIi is Integer ≥ 0)

B Flag indicating that the next fields and continuation entries contain viscous damping values until it is the end of the entry.

No default (Character)

Bmn Viscous damping matrix for degrees-of-freedom in GIi/CIi where “m” is the row number and “n” is the column number. Only the lower triangular terms in the matrix need to be specified. Zero values must be specified as blank or 0.0.

Default = 0.0 (Real)

Structural Damping Matrix: 8 9 10
GIi/CIi Grid (or scalar point) and component identification numbers ordered according to structural damping values specified in K4mn.

No default (GIi is Integer > 0 and CIi is Integer ≥ 0)

K Flag indicating that the next fields and continuation entries contain structural damping values until it is the end of the entry.

No default (Character)

K4mn Structural damping matrix for degrees-of-freedom in GIi/CIi where “m” is the row number and “n” is the column number. Only the lower triangular terms in the matrix need to be specified. Zero values must be specified as blank or 0.0.

Default = 0.0 (Real)

1. GIi/CIi and KZmn are required inputs. Either K or Z must be specified, but not both.
2. UD, K, Z, and S, may be specified in any order as demonstrated in the third example.
3. UD and S are optional inputs. S defines the motion between the GIi/CIi and GDj/CDj degrees-of-freedom according to:(1)
$\left\{{u}_{i}\right\}=\left[S\right]\left\{{u}_{d}\right\}$

But if S is specified, then GDj/CDj must also be specified. If S is not specified, then GDj/CDj may contain six and only six degrees-of- freedom and they cannot refer to SPOINTs.

4. If only K or Z is input without UD, then it is recommended that the resulting stiffness represents the unsupported element, containing all of the rigid body modes. If not, the UD option allows for the reintroduction of the rigid body modes with S which is provided by you or computed internally.
• If $K$ and UD are specified, the program will form the complete stiffness as defined by:(2)
$\left\{\begin{array}{c}{F}_{i}\\ {F}_{d}\end{array}\right\}=\left[\begin{array}{cc}K& –K S\\ –{S}^{T}K& –{S}^{T}K S\end{array}\right] \left\{\begin{array}{c}{u}_{i}\\ {u}_{d}\end{array}\right\}$

Where, the $K$ matrix is formed from the KZmn values and the S matrix is formed from the Sij values or computed automatically.

• If Z and UD are specified, then the program will form the complete stiffness as defined by: (3)
$\left\{\begin{array}{c}{F}_{i}\\ {F}_{d}\end{array}\right\}=\left[\begin{array}{cc}{Z}^{-1}& –{Z}^{-1} S\\ –{S}^{T}{Z}^{-1}& –{S}^{T}{Z}^{-1} S\end{array}\right] \left\{\begin{array}{c}{u}_{i}\\ {u}_{d}\end{array}\right\}$

Where, the Z matrix is formed from the KZmn values and the S matrix is formed from the Sij values or computed automatically. Z must be nonsingular.

5. PARAM, CK3 may be used to scale the stiffness produced by all GENEL elements.
6. All lower triangular values in K and Z and all values in S have to be accounted for in the input. Zero values may be specified as 0.0 or be left blank, however if all entries in any continuation line are zero, then at least one visible character must appear on this line (it can be 0.0 in any field or the plus sign (+) in the first column) because blank lines are treated as comment. Unused fields (after the last matrix entry) must be blank.
7. General elements are ignored in heat transfer analysis.
8. GIi/CIi and Mmn (or Bmn/K4mn) are required inputs.
9. UD” and “S” should not be defined along with Mass, Viscous Damping, or Structural Damping matrices.
10. Only lower triangular terms in the matrix should be input.