*HEADING STEADY STATE DYNAMICS PROCEDURES FOR 3D CONNECTORS WITH VISCOUS DAMPING ** *NODE, NSET=NALL 1,0.0,0.0, 2,1.0,0.0, 3,2.0,0.0, 4,3.0,0.0, *NSET, NSET=FIXED 1,4 *NSET, NSET=NODE2 2,3 *PARAMETER C=1.0 CS=0.1 KAXIAL1=1.0E3 U1=1.0E-3 KAXIAL2=KAXIAL1/10 U2=100*U1 F1=KAXIAL1*U1 F2=F1+KAXIAL2*(U2-U1) mF1=-F1 mF2=-F2 mU1=-U1 mU2=-U2 ** ** CONNECTOR ELEMENTS ** *ELEMENT, TYPE=CONN3D2, ELSET=AXIAL 1,1,2 2,2,3 *ELEMENT, TYPE=CONN3D2, ELSET=ACTUATOR 3,3,4 *ELSET, ELSET=CONNECTORS AXIAL,ACTUATOR ** ** MASS ELEMENTS ** *ELEMENT, TYPE=MASS, ELSET=MASS 1001,1 1002,2 1003,3 1004,4 ** ** SECTION DEFINITIONS ** *MASS, ELSET=MASS 1.0, *CONNECTOR SECTION, ELSET=AXIAL, BEHAVIOR= CB_AXIAL CARTESIAN *CONNECTOR SECTION, ELSET=ACTUATOR CARTESIAN ** ** CONNECTOR BEHAVIOR DEFINITIONS ** *CONNECTOR BEHAVIOR, NAME= CB_AXIAL *CONNECTOR ELASTICITY, COMPONENT=1, NONLINEAR , , , , *CONNECTOR DAMPING, COMPONENT=1, TYPE=VISCOUS , *CONNECTOR DAMPING, COMPONENT=1, TYPE=STRUCTURAL , ** ** BOUNDARY CONSTRAINTS (BASE STATE) ** *CONNECTOR MOTION AXIAL,2 AXIAL,3 ACTUATOR,2 ACTUATOR,3 *BOUNDARY NALL,4,6 FIXED,1,3 *** ** STEP 1 - FREQUENCY EXTRACTION USING AMS *** *STEP STEP-1: EXTRACT EIGENMODE ** *FREQUENCY, EIGENSOLVER=AMS, NORM=MASS, DAMPING PROJ=ON 2, ,30, ** *OUTPUT, FIELD *NODE OUTPUT U, *END STEP *** ** STEP 2 - MODE-BASED SSD *** *STEP STEP-2: MODE-BASED STEADY STATE DYNAMIC RESPONSE ** *STEADY STATE DYNAMICS, FREQUENCY SCALE=LINEAR, INTERVAL=RANGE 1, 20, 20 ** *CONNECTOR LOAD, LOAD CASE=1 ACTUATOR,1,-1.0 *CONNECTOR LOAD, LOAD CASE=2 ACTUATOR,1,-1.0 ** ** OUTPUT REQUEST ** *OUTPUT, FIELD *NODE OUTPUT U, V, A, *OUTPUT, HISTORY *NODE OUTPUT, NSET=NODE2 U, V, A, *NODE PRINT, NSET=NODE2 U1, V1, A1, *NODE PRINT, NSET=FIXED rf, *END STEP *STEP STEP-3: MODE-BASED STEADY STATE DYNAMIC RESPONSE ** *STEADY STATE DYNAMICS, FREQUENCY SCALE=LINEAR, INTERVAL=RANGE 1, 20, 20 ** *CONNECTOR LOAD, LOAD CASE=1 ACTUATOR,1,-1.0 *CONNECTOR LOAD, LOAD CASE=2 ACTUATOR,1,-1.0 *damping controls, viscous=none ** ** OUTPUT REQUEST ** *OUTPUT, FIELD *NODE OUTPUT U, V, A, *OUTPUT, HISTORY *NODE OUTPUT, NSET=NODE2 U, V, A, *NODE OUTPUT, NSET=FIXED RF, *NODE PRINT, NSET=NODE2 U1, V1, A1, *NODE PRINT, NSET=FIXED rf, *END STEP *STEP STEP-4: MODE-BASED STEADY STATE DYNAMIC RESPONSE ** *STEADY STATE DYNAMICS, FREQUENCY SCALE=LINEAR, INTERVAL=RANGE 1, 20, 20 ** *CONNECTOR LOAD, LOAD CASE=1 ACTUATOR,1,-1.0 *CONNECTOR LOAD, LOAD CASE=2 ACTUATOR,1,-1.0 *damping controls, viscous=none, structural=factor *global damping, structural=0.1 ** ** OUTPUT REQUEST ** *OUTPUT, FIELD *NODE OUTPUT U, V, A, *OUTPUT, HISTORY *NODE OUTPUT, NSET=NODE2 U, V, A, *NODE PRINT, NSET=NODE2 U1, V1, A1, *END STEP