!!! FEA H2: EXCENTRICALLY LOADED U-SECTION BEAM !! Initial setup ! Isometric view /VIEW,1,1,1,1 /ANG,1 /REP,FAST ! White canvas /RGB,INDEX,100,100,100,0 /RGB,INDEX,0,0,0,15 ! Constant parameters ! Units: [N],[Nmm],[N/mm^2=MPa],[N/mm] ELAST=2E5 NU=0.3 RHO=7.8e-9 T=10 F=3000 !! SETUP: element types, materials, layup KEYW,PR_STRUC,1 ! Preferences / Structural /PREP7 ET,1,SHELL181 ! MPTEMP MPTEMP,1,0 MPDATA,EX,1,,ELAST MPDATA,PRXY,1,,NU ! MPTEMP MPTEMP,1,0 MPDATA,DENS,1,,RHO ! ! Layup definition SECT,1,shell,, SECDATA, t,1,0.0,3 SECOFFSET,MID SECCONTROL ! ! Define keypoints K,1,0,0,0, K,2,0,0,1000, K,3,100,0,0, K,4,0,200,0, K,5,100,200,0, ! ! Create lines L,5,4 L,4,1 L,1,3 ! Linene along the beam axis L,1,2 ! Create the surface model by extruding the contour of the U-section ADRAG,1,2,3,,,,4 ! Connect the extruded areas AGLUE,ALL ! ! Set the number of elements on the lines LESIZE,1,,,10 LESIZE,2,,,20 LESIZE,3,,,10 LESIZE,5,,,10 LESIZE,6,,,60 LESIZE,7,,,60 LESIZE,8,,,20 LESIZE,9,,,60 LESIZE,10,,,10 ! ! Mesh the areas using mapped meshing algorithm MSHKEY,1 AMESH,ALL ! Reset mesh option MSHKEY,0 ! ! Select nodes at z = 0 NSEL,S,LOC,Z,0,0 ! ! Constrain all DoFs at this location D,ALL,ALL ,0 ! ALLSEL,ALL ! select nodes at x = 0, z = 1000 NSEL,S,LOC,X,0,0 NSEL,R,LOC,Z,1000,1000 ! Apply the calculated force at every node at this location F,ALL,FY,-F/21 ! Select everything ALLSEL,ALL FINISH ! ! Solve the finite element equation K.U = F /SOL SOLVE ! Post processing /POST1 ! Save the displaced structure as bmp PLNSOL, U,X, 0,1.0 /IMAGE,SAVE,disp_x,bmp PLNSOL, U,Y, 0,1.0 /IMAGE,SAVE,disp_y,bmp PLNSOL, U,Z, 0,1.0 /IMAGE,SAVE,disp_z,bmp ! Plott the stress values at the longitudinal edge of the beam ! x = 0, y = 0 PATH,2,2,30,100 PPATH,1,,0,0,0 PPATH,2,,0,0,1000 PDEF,SX,S,X,AVG PDEF,SY,S,Y,AVG PDEF,SZ,S,Z,AVG ! Save the stress distribution along the path as bmp PLPATH,SX /IMAGE,SAVE,sx,bmp ! PLPATH,SY /IMAGE,SAVE,sy,bmp ! PLPATH,SZ /IMAGE,SAVE,sz,bmp FINISH /SOL ! ! Modal analysis, first 10 natural frequencies ANTYPE,2 ! MODOPT,LANB,10,0,0, ,OFF EQSLV,SPAR MXPAND,10, , ,1 LUMPM,0 PSTRES,0 ! SOLVE FINISH ! /POST1 SET,FIRST ! Save the eigenshapes as bmp files *DO, III, 1, 10,1 PLNSOL, U,Y, 2,1.0 /IMAGE,SAVE,strcat(chrval(III),'_eigenshape'),bmp SET,NEXT *ENDDO