FLLWER

Bulk Data Entry

FLLWER – Parameters for Calculation of Loads Dependent on Deformation

Description

Define parameters for the calculation of loads dependent on deformation. Two type of loads, pressure load (only PLOAD4 bulk data entries) and concentrated force (only FORCE1/FORCE2 bulk data entries) can use this entry to control the options for Follower Loads.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
FLLWER	ID	OPT

The following continuation line is used to define another set of follower force parameters, which overrides the set of parameters above, for a specific follower load interface. It can be repeated as required.

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
+	LOADSET	OPT	LSID1	LSID2	LSID3	LSID4

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
FLLWER	99	2

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
FLLWER	99
+	LOADSET	-1	8	12	13
+	LOADSET	1	9	14	15	16
+	LOADSET	2	10	17	19	20	21
+	22	23	24

Field	Contents
ID	Each FLLWER bulk data card must have a unique ID. No default (Integer > 0)
OPT	Options for the calculation for Follower Loads. Default = 1 <-1, 0, 1, 2, or 3> = -1, 0: Follower force calculation is not activated. = 1: Follower effect is activated. For pressure load, both element surface area and load direction are involved to calculate follower force. For concentrated force, only the force direction is involved. = 2: Follower effect is activated. For pressure load, only element surface area is involved. For concentrated force, only the force direction is involved (same effect as FLLWER = 1). = 3: Follower effect is activated. For pressure load, only load direction is involved. For concentrated force, only the force direction is involved (same effect as FLLWER = 1).
LSIDi	Identification number of a PLOAD4 or FORCE1/FORCE2 Bulk Data Entry. No default (Integer > 0)

Comments

1.	The FLLWER bulk data entry is selected by the Subcase Information command FLLWER = option.

2.	Follower force is currently only supported for large-displacement nonlinear static analysis subcases.

3.	Continuation (by use of entry CNTNLSUB) of a nonlinear solution from a preceding nonlinear subcase is supported. However, if a load set is applied in both subcases, the FLLWER option of the load set must be exactly the same in the two subcases.

4.	It is recommended to use hash assembly for subcases with follower loads. This is activated using PARAM,HASHASSM,YES.

5.	Follower load stiffness is generally un-symmetric. OptiStruct supports both symmetric solvers and un-symmetric solvers for follower loadcase. Un-symmetric solver is activated using PARAM,UNSYMSLV,YES.

6.	BCS solver should not be used with PARAM,HASHASSM,YES with PARAM,UNSYMSLV,YES for follower load subcases. The MUMPS solver should not be used with PARAM,HASHASSM,NO.

7.	This card is represented as a loadcollector in HyperMesh.