/COM,ANSYS MEDIA REL. 2024R2 (05/10/2024) REF. VERIF. MANUAL: REL. 2024R2 /VERIFY,VM252 /TITLE,VM252,GURSON BAR-NECKING BENCHMARK WITH APPLIED DISPLACEMENT /COM, REFERENCE: /COM, N. ARAVAS, "ON THE NUMERICAL INTEGRATION OF A CLASS OF PRESSURE /COM, DEPENDENT PLASTICITY MODELS." INT. J. FOR NUMERICAL METHODS IN /COM, ENGINEERING. VOLUME. 24, PP. 1395-1416 (1987) /COM, SECTION 5.3, FIGURE 10. ! DEFINED CONSTANTS PI=3.141592654 MYSUBST=100 ! NUMBER OF SUBSTEPS FOR SOLUTION UAPP=0.7602 ! APPLIED DISPLACEMENT R0=1 ! WIDTH OF ROD DR0=0.005*R0 ! NODE OFFSET TO CREATE NOTCH L0=4.0*R0 ! LENGTH OF MODEL YOUNG=1000000 ! YOUNG'S MODULUS NU=0.3 ! POISSON RATIO ! GURSON COEFFICIENTS Q1=1.5 ! FIRST TVERGAARD CONSTANT Q2=1 ! SECOND TVERGAARD CONSTANT Q3=Q1*Q1 ! THIRD TVERGAARD CONSTANT SIGMA_Y=YOUNG/300.0 ! YIELD STRESS YIELD=1.0D0/SIGMA_Y/PI/R0/R0 ! YIELD STRENGTH F_0=1E-8 ! INITIAL POROSITY F_N=0.04 ! VOLUME FRACTION/ VOID NUCLEATION S_N=0.1 ! STANDARD DEV. OF MEAN STRAIN FOR NUCLEATION. STRAIN_N=0.3 ! MEAN STRAIN FOR NUCLEATIONS POWER_N=0.1 ! FOR ELASTIC MATERIAL DEFINITION /PREP7 MP,EX,1,YOUNG ! MATERIAL PROPERTIES MP,NUXY,1,NU TB,NLISO,1,1,2,5 ! ELASTIC MODEL TBDATA,1,SIGMA_Y,POWER_N TB,GURS,1,,5,BASE ! BASE DEFINED TBDATA,1,SIGMA_Y,F_0,Q1,Q2,Q3 TB,GURS,1,,3,SNNU ! SNNU DEFINED TBDATA,1,F_N,STRAIN_N,S_N ET,1,PLANE182,,,1 ! AXISYMMETRIC 2D RECT,0,R0,0,L0/8 ! DEFINE GEOMETRY AND MESH RECT,0,R0,L0/8,L0 AGLUE,ALL LSEL,S,LOC,X,R0/2 LESIZE,ALL,,,10 LSEL,S,LOC,Y,L0/16 LESIZE,ALL,,,5 LSEL,S,LOC,Y,L0/8,L0 LESIZE,ALL,,,20,4 SAVE,MODEL AMESH,ALL MODMSH,DETACH NMODIF,NODE(R0,0,0),R0-DR0,0,0 ! TO CREATE NOTCH AT BOTTOM OF ROD NSEL,S,LOC,X,0 ! BOUNDARY CONDITIONS D,ALL,UX,0 NSEL,S,LOC,Y,0 D,ALL,UY,0 ALLS NSEL,S,LOC,Y,L0 D,ALL,UY,UAPP ALLS FINISH *CREATE,MACRO,MAC ! MACRO FOR SOLUTION AND POST PROCESSING /SOLU ! NON-LINEAR SOLUTION OUTRES,ALL,ALL NLGEOM,ON NROPT,UNSYM NSUBST,MYSUBST,MYSUBST,MYSUBST ALLS /OUTPUT,SCRATCH SOLVE /OUT FINISH /POST1 ! REACTION FORCES AT TOP OF BAR *DIM,X,ARRAY,MYSUBST *DIM,Y,ARRAY,MYSUBST *DO,J,1,MYSUBST SET,1,J *GET,DISPY,NODE,NODE(R0,L0,0),U,Y X(J)=LOG(1+DISPY/L0) ! AS DEFINED BY REFERENCE TOTFORCE=0.0D0 NSEL,ALL ESLN NSLE *GET,NNODE,NODE,,COUNT *DO,K,1,NNODE *IF,NY(K),EQ,4.0,THEN *GET,NFOR,NODE,K,RF,FY TOTFORCE=TOTFORCE+NFOR ! TOTAL FORCE *ENDIF *ENDDO Y(J)=TOTFORCE*YIELD ! Y DATA TO BE PLOTTED *ENDDO MAXIMUM=0.01 ! LOOP TO DETERMINE MAXIMUM IN VECTOR Y *DO,KK,1,MYSUBST,1 *IF,Y(KK),LT,MAXIMUM,THEN MAXIMUM=Y(KK-1) *EXIT *ELSE MAXIMUM=Y(KK) KK=KK+1 *ENDIF *ENDDO /AXLAB,Y,NORMALIZED LOAD *VPLOT,X(1),Y(1) *DIM,VALUE,ARRAY,1,3 *DIM,LABEL,CHAR,1,1 LABEL(1) = 'LOADING' *VFILL,VALUE(1,1),DATA,1.25 *VFILL,VALUE(1,2),DATA,MAXIMUM *VFILL,VALUE(1,3),DATA,1.25/MAXIMUM *END MACRO SAVE,TABLE_1 RESUME,MODEL /PREP7 ET,1,PLANE183,,,1 AMESH,ALL MODMSH,DETACH NMODIF,NODE(R0,0,0),R0-DR0,0,0 ! TO CREATE NOTCH AT BOTTOM OF ROD NSEL,S,LOC,X,0 ! BOUNDARY CONDITIONS D,ALL,UX,0 NSEL,S,LOC,Y,0 D,ALL,UY,0 ALLS NSEL,S,LOC,Y,L0 D,ALL,UY,UAPP ALLS FINISH MACRO SAVE,TABLE_2 RESUME,TABLE_1 /COM, /OUT,vm252,vrt /COM,--------------- VM252 RESULTS COMPARISON ------------------- /COM, /COM, | TARGET | Mechanical APDL | RATIO | /COM, /COM,PLANE182 RESULTS COMPARISON *VWRITE,LABEL(1),VALUE(1,1),VALUE(1,2),VALUE(1,3) (1X,A8,' ',F8.4,' ',F14.4,' ',1F15.3) /NOPR RESUME,TABLE_2 /GOPR /COM, /COM,PLANE183 RESULTS COMPARISON *VWRITE,LABEL(1),VALUE(1,1),VALUE(1,2),VALUE(1,3) (1X,A8,' ',F8.4,' ',F14.4,' ',1F15.3) /COM,------------------------------------------------------------ /OUT FINISH *LIST,vm252,vrt /DELETE,TABLE_1 /DELETE,TABLE_2