Input File Format

It contains several blocks of data which must be input in the right order. Each line beginning with '#' is considered a comment line and is not taken into account.

Data block 1: General data

#FORMAT: (7I8)
#  Nbmod   Nbstat   Nbnod   Irot   Idamp   Iblo   Ifile
     45       15      18      1       0      1       0

Field	Descripton	SI Unit Example
`Nbmod`	Total number of reduction modes
`Nbstat`	Number of static modes Note: Static modes are modes which are not orthogonal with respect to the stiffness. Their number gives the dimension of the full part of the local projected stiffness matrix. The number of so-called dynamic modes, given by (`Nbmod` - `Nbstat`) determines the size of the diagonal part of the local projected stiffness matrix.
`Nbnod`	Number of nodes in the flexible body support.
`Irot`	0 Flexible body contains no elements with rotational DOF 1 Flexible body contains elements with rotational DOF
`Idamp`	0 No Rayleigh damping is used on the flexible body. 1 Rayleigh damping is used on the flexible body.
`Iblo`	0 Flexible body is free of blockage and its finite overall rotations and translations are computed. 1 Flexible has no rigid body modes. Note: A flexible body is either fully free or fully blocked. A number of rigid body modes different from 0 or 6 in the local stiffness matrix is not permitted.
`Ifile`	0 All components of the modes and of the modal stress fields computed by Radioss Starter are stored in central memory. 1 Only the components of the attached to interface nodes of the flexible body (that is, nodes connected to the rest of the structure) are stored in central memory. The other components of the modes and all components of the modal stress fields computed by Radioss Starter, needed only for outputs, are stored on disk.

Data block 2: List of nodes

#FORMAT: (10I8)
#  Nodes
     21      22      23      24      25      26      27      28      29      30
     31      32      33      34      35      36      37      38

Description

The number of nodes in the list must be equal to Nbnod given in Data block 1. The order of nodes in the list is the order in which the sets of components of the projection modes are given in Data blocks 5, 6, and 7.

Data block 3: Initial rotation matrix and local maximum frequency

#FORMAT: (1P5E16.9)
#         Mrot11          Mrot12          Mrot13          Mrot21          Mrot22
1.000000000E+00 0.000000000E+00 0.000000000E+00 0.000000000E+00 1.000000000E+00
#         Mrot23          Mrot31          Mrot32          Mrot33            Freq
0.000000000E+00 0.000000000E+00 0.000000000E+00 1.000000000E+00 2.049574631E+04

Field	Descriptio	SI Unit Example
`Mrotij`	Component `P`_\|\| of the initial rotation matrix from the local frame of the flexible body to the global frame. Note: Matrix `P` defines the initial orientation of the flexible body.
`Freq`	Maximum eigen frequency of the local reduced system composed of local reduced mass matrix and local reduced stiffness matrix. Note: This frequency is used to compute the stability time step of the flexible body through the formula: $Δ t_{s t a b} = \frac{1}{π \cdot F r e q}$

Data block 4: Damping data (optional, present only if `Idamp` = 1)

#FORMAT: (1P2E16.9)

#         Alpha			    Beta

1.092357846E+01		4.652573369E-07

Description:

Field	Description	SI Unit Example
`Alpha`, `Beta`	Rayleigh damping coefficients Note: Local damping matrix is obtained from local reduced mass and stiffness matrices through the formula: $C_{L} = A l p h a \cdot M_{L} + B e t a \cdot K_{L}$

Data block 5: Projection modes - Modes representing the overall rigid body motion of the flexible body (optional, present only if `Iblo` = 0)

#FORMAT: (1P5E16.9)
#   1         X              Y                Z              XX              YY
#FORMAT: (1P1E16.9)
#            ZZ
0.000000000E+00-1.250000000E+01 0.000000000E+00 0.000000000E+00 0.000000000E+00
0.000000000E+00
0.000000000E+00 1.250000000E+01 0.000000000E+00 0.000000000E+00 0.000000000E+00
0.000000000E+00
...

Description

12 modes

Φ_{R}^{i}

with

i

=1…12 are input by blocks of Nbnod sets of six values (one set for each node of the support of the flexible body).

Field	Description	SI Unit Example
`X`, `Y`, `Z`	Components of the mode on the translational DOF of the node.
`XX`, `YY`, `ZZ`	Components of the mode on the rotational DOF of the node 0 If the node has no rotational DOF.

Data block 6: Projection modes - Modes accounting for the inertia associated with the rotational degrees of freedom (optional, present only if `Iblo` = 0 and `Irot` = 1)

Example

Same format as Data block 5

Description

3 modes $Φ_{R}^{12 + i}$ with $i$ =1…3 are input by blocks of Nbnod sets of six values.

Data block 7: Projection modes - Local reduction modes

Example

Same format as Data block 5

Description

Nbmod modes $Φ_{L}^{i}$ with $i$ =1…Nbmod are input by blocks of Nbnod sets of six values. The Nbstat static modes are given first.

Data block 8: Local reduced diagonal mass matrix

#FORMAT: (1P5E16.9)
5.596016869E+03   8.234274572E+03  2.320889319E+04  1.215104250E+03  1.729160225E+02
3.000458618E+05   3.074228932E+02  1.458647403E+04  1.425398877E+02  4.251072139E+05

Description

Nbmod values are entered, following the order in which the local modes are given.

Data block 9: Local reduced stiffness matrix - Full part

Example

Same format as Data block 8

Description

The shape of the matrix to input is: [Mat_sym Mat_rect]. The dimension of Mat_sym is Nbstat. The dimensions of Mat_rect are Nbstat * (Nbmod - Nbstat). The following order for input the terms is followed (for example: Nbmod = 6 and Nbstat = 3):(1)

[\begin{matrix} 1 & 2 & 3 & 4 & 5 & 6 \\ 7 & 8 & 9 & 10 & 11 \\ 12 & 14 & 15 & 16 \end{matrix}]

It corresponds to a skyline storage of the Nbstat first lines of the local reduced stiffness matrix. The number of terms to input is $\frac{1}{2} N b s t a t (2 N b m o d - N b s t a t + 1)$ . Again, the numbering of the columns of the matrix follows the order in which the local modes are given.

Data block 10: Local reduced stiffness matrix - Diagonal part

Example

Same format as Data block 8

Description

(Nbmod - Nbstat) values are entered, following the order in which the local dynamic modes are given.

Data block 11: Mass matrix projected on the modes defining the rigid body motion (optional, present only if `Iblo` = 0)

Example

Same format as Data block 8

Description

This is a full symmetric matrix entered using a skyline storage. Column numbering follows the order in which the modes defining the rigid motion are given. The dimension of the matrix is 12, if Irot = 0 or 15, if Irot = 1. Thus, the number of values to input is equal to 78, if Irot = 0 or 120, if Irot = 1.

Data block 12: Matrices for coupled mass projection (optional, present only if `Iblo` = 0)

Example

Same format as Data block 8

Description

Nine sub-blocks are given, one for each constant contribution $M_{C k 1}$ . These are rectangular matrices. The number of lines is equal to 12, if Irot = 0 or 15, if Irot = 1. The number of columns is Nbmod. The terms of the matrices are entered line by line. Their number is equal to 12*Nbmod, if Irot = 0 or 15*Nbmod, if Irot = 1.

Data block 13: Matrices for coupled stiffness projection (optional, present only if `Iblo` = 0)

Example

Same format as Data block 8

Description

Nine sub-blocks are given, one for each constant contribution $K_{C k 1}$ . These are rectangular matrices. The number of lines is equal to 12, if Irot = 0 or 15, if Irot = 1. The number of columns is Nbmod. The terms of the matrices are entered line by line. Their number is equal to 12*Nbmod, if Irot = 0 or 15*Nbmod, if Irot = 1.

Input File Format

Data block 1: General data

Data block 2: List of nodes

Data block 3: Initial rotation matrix and local maximum frequency

Data block 4: Damping data (optional, present only if Idamp = 1)

Data block 5: Projection modes - Modes representing the overall rigid body motion of the flexible body (optional, present only if Iblo = 0)

Data block 6: Projection modes - Modes accounting for the inertia associated with the rotational degrees of freedom (optional, present only if Iblo = 0 and Irot = 1)

Data block 7: Projection modes - Local reduction modes

Data block 8: Local reduced diagonal mass matrix

Data block 9: Local reduced stiffness matrix - Full part

Data block 10: Local reduced stiffness matrix - Diagonal part

Data block 11: Mass matrix projected on the modes defining the rigid body motion (optional, present only if Iblo = 0)

Data block 12: Matrices for coupled mass projection (optional, present only if Iblo = 0)

Data block 13: Matrices for coupled stiffness projection (optional, present only if Iblo = 0)

Data block 4: Damping data (optional, present only if `Idamp` = 1)

Data block 5: Projection modes - Modes representing the overall rigid body motion of the flexible body (optional, present only if `Iblo` = 0)

Data block 6: Projection modes - Modes accounting for the inertia associated with the rotational degrees of freedom (optional, present only if `Iblo` = 0 and `Irot` = 1)

Data block 11: Mass matrix projected on the modes defining the rigid body motion (optional, present only if `Iblo` = 0)

Data block 12: Matrices for coupled mass projection (optional, present only if `Iblo` = 0)

Data block 13: Matrices for coupled stiffness projection (optional, present only if `Iblo` = 0)