Hello!<\/p>\n
I have a geometry model of a structure made of beam elements(BEAM181) with few lumped masses (MASS21) and 1D springs-damper(COMBIN14) acting on different DOF with both linear and nonlinear damping. I ran this geometry first in a modal analysis encountering no errors. Now I am trying with the transient analysis that would be final goal for the research but it gave the following errorin the at LSSOLVE command: node I and J for element [COMBIN14 element number] are not coincident. I tried to fix it by putting the second node of the element at the same location but I still have problems, and I did not find any clear requirement in the Element Reference that the nodes have to be coincident. Do they have to be? Does anyone know how to fix this code?<\/p>\n
Here are the MAPDL lines where I define this elements:<\/p>\n
lumped mass element -> floaters (3d with rotary inertia + coordinate system parallel to node)
et,2,mass21,0,0,0<\/p>\n
!elements -> damping & stiffness of floaters
et,3,combin14,,1 !spring-damper ux (mooring stiffness)
et,5,combin14,,2 !spring-damper uy (mooring stiffness)
et,4,combin14,,3 !spring-damper uz (mooring stiffness+ heave c33)
et,6,combin14,,4 !spring-damper rotx (pitch c44)
et,7,combin14,,5 !spring-damper roty (roll c55)<\/p>\n
!connectors
et,9,combin14,1,1
et,10,combin14,1,2
et,11,combin14,1,3
et,12,combin14,1,4
et,13,combin14,1,5
et,14,combin14,1,6<\/p>\n
!! define nodes for lumped masses
!floaters masses COG
!left down
n,1,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),h_fl_up\/2
n,2,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_down\/2
n,3,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_down+T_fl\/2 !added mass
!right down
n,4,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),h_fl_up\/2
n,5,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_down\/2
n,6,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_down+T_fl\/2 !added mass
!centre up
n,7,L_tot\/2,(L_t-L_obl)*sin(pi\/3),h_fl_up\/2
n,8,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_down\/2
n,9,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_down+T_fl\/2 !added mass
!! define nodes for hd spring-damper second nodes
!left down
n,10,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+T_fl\/12
n,11,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+2*T_fl\/12
n,12,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+3*T_fl\/12
n,13,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+4*T_fl\/12
n,14,-L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+5*T_fl\/12
!right down
n,15,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+T_fl\/12
n,16,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+2*T_fl\/12
n,17,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+3*T_fl\/12
n,18,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+4*T_fl\/12
n,19,L_tot+L_obl\/2*cos(pi\/3),L_obl\/2*sin(pi\/3),-h_fl_tot+5*T_fl\/12
!centre up
n,20,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_tot+T_fl\/12
n,21,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_tot+2*T_fl\/12
n,22,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_tot+3*T_fl\/12
n,23,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_tot+4*T_fl\/12
n,24,L_tot\/2,(L_t-L_obl)*sin(pi\/3),-h_fl_tot+5*T_fl\/12
!define nodes for mass connectors
n,25,-L_obl\/2*cos(pi\/3)-dist_conn*cos(angle_conn),L_obl\/2*sin(pi\/3)+dist_conn*sin(angle_conn),h_fl_up\/2
n,26,L_tot+L_obl\/2*cos(pi\/3)+dist_conn*cos(angle_conn),L_obl\/2*sin(pi\/3)+dist_conn*sin(angle_conn),h_fl_up\/2
n,27,L_tot\/2-dist_conn*cos(angle_conn),(L_t-L_obl)*sin(pi\/3)+dist_conn*sin(angle_conn),h_fl_up\/2
n,28,L_tot\/2+dist_conn*cos(angle_conn),(L_t-L_obl)*sin(pi\/3)+dist_conn*sin(angle_conn),h_fl_up\/2
!second nodes spings mass connector
n,29,-L_obl+L_obl\/2*cos(a),L_obl\/2*sin(a),0
n,30,L_tot+L_obl-L_obl\/2*cos(a),L_obl\/2*sin(2*a),0
n,31,L_tot*cos(a)-L_obl\/2*cos(a),L_obl*sin(2*a)+L_tot*sin(a)+L_obl\/2*sin(a),0
n,32,L_tot-L_tot*cos(a)+L_obl\/2*cos(a),L_obl*sin(2*a)+L_tot*sin(a)+L_obl\/2*sin(a),0<\/p>\n
!lumped masses for floaters
type,2
!up
real,1
en,1,1
en,2,4
en,3,7
r,1,m_fl_up,m_fl_up,m_fl_up,I_fl_xx_up,I_fl_yy_up,I_fl_zz_up<\/p>\n
!down
real,2
en,4,2
en,5,5
en,6,8
r,2,m_fl_down,m_fl_down,m_fl_down,I_fl_xx_down,I_fl_yy_down,I_fl_zz_down<\/p>\n
!added mass
real,3
en,7,3
en,8,6
en,9,9
r,3,m_xx,m_yy,m_zz,I_xx,I_yy,I_zz <\/p>\n
!spring-damper element for floaters
type,3 !spring-damper ux (mooring stiffness)
real,4
en,10,3,10
en,11,6,15
en,12,9,20
r,4,c_x,0<\/p>\n
type,4 !spring-damper uy (mooring stiffness)
real,5
en,13,3,11
en,14,6,16
en,15,9,21
r,5,c_y,0<\/p>\n
type,5 !spring-damper uz (mooring stiffness+ heave c33)
real,6
en,16,3,12
en,17,6,17
en,18,9,22
r,6,c_z+c_33,0<\/p>\n
type,6 !spring-damper rotx (pitch c44)
real,7
en,19,3,13
en,20,6,18
en,21,9,23
r,7,c_44,0<\/p>\n
type,7 !spring-damper roty (roll c55)
real,8
en,22,3,14
en,23,6,19
en,24,9,24
r,8,c_55,0<\/p>\n
!lumped masses connectors
type,2
real,9
en,25,25
en,26,26
en,27,27
en,28,28
r,9,m_tot_ccs\/2<\/p>\n
!springs connectors
!ux
type,9
real,10
en,29,25,29
en,30,26,30
en,31,27,31
en,32,28,32
r,10,k_conn,b1_conn,b2_conn<\/p>\n
!uy
type,10
real,11
en,33,25,29
en,34,26,30
en,35,27,31
en,36,28,32
r,11,k_conn,b1_conn,b2_conn<\/p>\n
!uz
type,11
real,12
en,37,25,29
en,38,26,30
en,39,27,31
en,40,28,32
r,12,k_conn,b1_conn,b2_conn<\/p>\n
!rotx
type,12
real,13
en,41,25,29
en,42,26,30
en,43,27,31
en,44,28,32
r,13,k_conn,b1_conn,b2_conn<\/p>\n
!roty
type,13
real,14
en,45,25,29
en,46,26,30
en,47,27,31
en,48,28,32
r,14,k_conn,b1_conn,b2_conn<\/p>\n
!rotz
type,14
real,15
en,49,25,29
en,50,26,30
en,51,27,31
en,52,28,32
r,15,k_conn,b1_conn,b2_conn<\/p>\n
!—-
!linking floaters lumped masses to structure
!—
!left down
ksel,s,kp,,1
ksel,a,kp,,23
ksel,a,kp,,11
ksel,a,kp,,53
nslk,s
rbe3,1,all,all
rbe3,2,all,all
rbe3,3,all,all<\/p>\n
!right down
ksel,s,kp,,5
ksel,a,kp,,14
ksel,a,kp,,6
ksel,a,kp,,37
nslk,s
rbe3,4,all,all
rbe3,5,all,all
rbe3,6,all,all<\/p>\n
!centre up
ksel,s,kp,,18,19,1
ksel,a,kp,,50,51,1
nslk,s
rbe3,7,all,all
rbe3,8,all,all
rbe3,9,all,all<\/p>\n
!—-
!linking connectors lumped masses to structure
!—<\/p>\n
!left down
ksel,s,kp,,23
ksel,a,kp,,33
ksel,a,kp,,53
nslk,s
rbe3,25,all,all<\/p>\n
!right down
ksel,s,kp,,14
ksel,a,kp,,36
ksel,a,kp,,37
nslk,s
rbe3,26,all,all<\/p>\n
!centre up left
ksel,s,kp,,18
ksel,a,kp,,51,52,1
nslk,s
rbe3,27,all,all<\/p>\n
!centre up right
ksel,s,kp,,19
ksel,a,kp,,50,52,2
nslk,s
rbe3,28,all,all<\/p>\n
!———-
!constraints springs for floaters hydro properties
!———-<\/p>\n
!constraints on second node
nsel,s,node,,10,20,5
d,all,ux,0<\/p>\n
nsel,s,node,,11,21,5
d,all,uy,0<\/p>\n
nsel,s,node,,12,22,5
d,all,uz,0<\/p>\n
nsel,s,node,,13,23,5
d,all,rotx,0<\/p>\n
nsel,s,node,,14,24,5
d,all,roty,0<\/p>\n
!———-
!constraints springs for connectors
!———-<\/p>\n
!constraints on second node
nsel,s,node,,25,28,1
d,all,ux,0
d,all,uy,0
d,all,uz,0
d,all,rotx,0
d,all,roty,0
d,all,rotz,0<\/p>\n","protected":false},"template":"","class_list":["post-367683","topic","type-topic","status-closed","hentry","topic-tag-ansys-error","topic-tag-combin14","topic-tag-point-mass-1","topic-tag-rbe","topic-tag-transient-analysis","topic-tag-transient-structural"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["349018","20905"],"_bbp_author_ip":["184.24.96.177"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["880"],"_bbp_topic_status":["unanswered"],"_edit_lock":["1716298762:310850"],"_bbp_topic_id":["367683"],"_bbp_forum_id":["27791"],"_bbp_engagement":["20905","349018"],"_bbp_voice_count":["2"],"_bbp_reply_count":["5"],"_bbp_last_reply_id":["368112"],"_bbp_last_active_id":["368112"],"_bbp_last_active_time":["2024-05-22 16:37:09"]},"test":"e-vezzanistudent-tudelft-nl"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/367683","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":2,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/367683\/revisions"}],"predecessor-version":[{"id":367860,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/367683\/revisions\/367860"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=367683"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}