Assignment 5 - Crash Worthiness Analysis - Experimentation on crush tube analysis based on different contact types and indepth options

Target element size is 6 mm

The bumper mesh is being done by QI optimize this time I have already set the parameters and created the mesh

Table comparison b/w 11 cases -

	deformation	Plastic strain	Von-Mises stress	Contact Energy	KE	Internal Energy	Total Energy	Rigid Wall Forces	Rigid Body Master Node Displacement	Rigid Body Master Node Forces
inact-6	274.1	0.9705	0.595	0-MIn 2500-Max	0-MIn 45000-Max	0-min 42000-Max	42000-Min 45000-Max	0 - Min 1050 - Max	Z-max-275	Z-Max - 1050 Xmax- 25 Ymax-25
Inacti-6 with wall depth 180mm	274.1	0.9705	0.595	0-MIn 2500-Max	0-MIn 45000-Max	0-min 42000-Max	42000-Min 45000-Max	0 - Min 1050 - Max	Z-max-275	Z-Max - 1050 Xmax- 25 Ymax-25
As it is result	280	1.204	0.6964	0-MIn 2500-Max	0-MIn 45000-Max	0-min 42000-Max	42000-Min 45000-Max	0 - Min 1350- Max	Z-max-280	Z-Max - 1350 Xmax- 0 Ymax-0
Removed type 7 contact	335.9	1.299	0.769	0	17500-Min 45000-Max	0-Min 16250-Max	45000-constant	-125 - Min -45 - Max	Z-max- -335.9	Z-Max - 123 Xmax- -5 Ymax-2
Adding type 11 but selecting half in master and half in slave	266.3	0.9709	0.6049	0-Min 4000-Max	0-MIn 45000-Max	0-Min 39000-Max	39000-Min 45000-Max	0 - Min 1000- Max	Z-max- 266.3	Z-Max - 1100 Xmax- 8 Ymax-50
Selecting all components in type11 master and slave	263.8	0.8953	0.6141	0-Min 4000-Max	0-MIn 45000-Max	0-Min 39000-Max	39000-Min 45000-Max	0 - Min 1090- Max	Z-max- 263.8	Z-Max - 1190 Xmax- 30 Ymax-50
Selecting all components in type 11 but Igap value 1000	268.2	0.9515	0.5964	0-Min 3000-Max	0-MIn 45000-Max	0-Min 41000-Max	41000-Min 45000-Max	0 - Min 990- Max	Z-max- 268.2	Z-Max - 1000 Xmax- 20 Ymax-20
In above case removing type 7 contact and selecting I gap 1000	264	0.9244	0.6222	0-Min 4000-Max	0-MIn 45000-Max	0-Min 40000-Max	40000-Min 45000-Max	0 - Min 1080- Max	Z-max- 264	Z-Max - 1150 Xmax- 30 Ymax-60
Without notch and BC	264	0.9893	0.6125	0-Min 3000-Max	0-MIn 45000-Max	0-Min 41500-Max	41500-Min 45000-Max	0 - Min 780- Max	Z-max- 264	Z-Max - 680 Xmax- -30 Ymax-100
Creating mid notch	276.8	1.062	0.6529	0-Min 3500-Max	0-MIn 45000-Max	0-Min 38000-Max	38000-Min 45000-Max	0 - Min 850- Max	Z-max- 276.8	Z-Max - 950 Xmax- -30 Ymax--35
Creating notch on the opposite faces	277.9	0.9683	0.5098	0-Min 3500-Max	0-MIn 45000-Max	0-Min 39500-Max	39500-Min 45000-Max	0 - Min 850- Max	Z-max- 277.9	Z-Max - 850 Xmax- -50 Ymax-100

First Case is AS IT IS case -

Deformation with type 7 and type 2 contact without detailed inputs

plastic strain output

von-mises-stress

energy curves

rigid-wall-forces

rigid-body-forces

SECOND CASE IS ADDING INACTI-6 -

In this case inacti=6 is added and friction value is added so if you notice its slipping more and expanding more at the bottom side as compared to the above case and total deformation dropped by 6mm which means inacti=6 has stopped too much penetration

plastic strain is also lower in this case due to inacti=6

stress value also dropped

energy curves

rigid-wall-forces

rigid-body-forces

seam weld interface forces

node-to-surface-interface-forces

THIRD CASE INACTI=6 AND INCREASING RIGID WALL DEPTH TO 180 MM -

There was no change in any result when the rigid wall depth was increased beyond the notch every single data is same as the previous case so I am not adding its result its mentioned in the trable above

FOURTH CASE IS REMOVING THE TYPE 7 CONTACT FROM AS IT IS CASE -

Here as seen there is no type 7 contact and and elements are slipping through each other

plastic strain

von-misses-stress

energy-curves

rigid-wall-forces

FIFITH CASE IS ADDING TYPE 11 CONTACT IN INACTI=6 CASE BUT HALF OF COMPONENTS SELECTED AS MASTER AND HALF AS SALVE-

here the deformation is much ralistic as the bottom is not expanding unrealistically as was in inacti=6 but due to type-11 contact penetration is even lower so the total deformation also decreased by 8 mm

plastic strain value is incresed by a very lower value

von-misses stress value also increased

as observed through the graph internal energy value dropped by value of 2000 as comparted to inact=6 case

rigid wall forces dropped then inacti=6 case because of less penetration the material deforms more instead of pushing to the wall

interface forces

rigid body forces is same as that of inacti=6 case

SIXTH CASE IS WHEN SELECTING ALL COMPONENTS IN MASTER AND ALL IN SLAVE IN TYPE -11 CONTACT -

Due to I gap parameter in type 11 contact the penetration is lowered b/w edge to edge and as a result the total deformation value is dropped by 3 mm approx is was there is previous case but here all the components are selected in master and slave due to which this result is coming

plastic strain value is also decresed than the previous case

von misses stress value is incresed slightly in this case

internal energy is bit higher here i.e by 1000 than the previous case

rigid wall forces are slightly higher in this case

interface forces is highly fluctuating in this case than all the above cases

SEVENTH CASE WITH ABOVE CASE JUST IGAP VALUE IS CHOSEN AS 4 TH OPTION 1000 AS IN TYPE 7 ALREADY GIVEN -

Again same slip pattern at the bottom is happening i.e expanding at the bottom but total deformation has increased by 2 mm

plastic strain value has increased significatly by 0.1

von mises stress value slightly decresed

internal energy is 41000 which is higher than previous case but contact energy is lower than previous case

rigid wall forces are also lowered

rigid body forces

interface forces are behaving weird in this case the fluctuations are more at the end of simulation while its was from the starting itself in the previous case and pretty much no interface interaction at the starting zone of the simulation.

EIGHT CASE WITH ABOVE SITUATION TYPE 11 AND I GAP CONDITION SAME BUT REMOVING TYPE 7 CONTACT LETS SEE THE BEHAVIOUR -

total deformation value dropped by 2mm

plastic strain slightly dropped by 0.03

in this case is the second highest value of stress from all the above cases

just the contact energy is increased from the previous case

rigid wall forces a bit higher thena the previous case

rigid body forces

this seems alright as compared to the previous case as its happening from the starting till the end

WITHOU NOTCH AND BC BUT ALL CONTACTS ARE GIVEN -

Max deformation recorrded is 264mm

plastic strain is highest in this case than all the above

von misses stress

internal energy is slightly increased and contact energy is slightly decreased

rigid wall forces is the least in this case

rigid body forces

interface forces having the highest peaks

CREATING MIDDLE NOTCHWITHOUT BC WITH ALL THE CONTACTS-

This is having the highrst total deformation in all the above cases i.e 278.8

also the plastic strain is also increased from the previous case

this is also having the highest von misses stress in all the above cases

internal energy is dropped significantly and contact energy is almost the same

rigid wall forces are least in this case

rigid body forces

highest peaks in interface forces

NOW CREATING NOTCH ONLY ON THE OPPSITE FACE WITHOUT BC AND WITH ALL CONTACTS -

these notches can be used to control the type of deformation and which portion to deform first, controlling crumple time and behaviour, here this notch acted as a rib which itself did not further deform but controlled the deormation in its adjacent zones

plastic deformation is dropped from the previuous case

von mises stress is also dropped

internal energy is almost the same incresed very slightly and contact energy is almost the same

rigid wall forces increased a bit

rigid body forces

interface forces

The reason why internal energy is changing because of the interaction b/w different enetities depends whether we are giving node to surface contact,edge to edge contact, weld interactioin, parameters of initial penetration due to these properties imaginary springs are formed which is in turn changing internal energies of the whole sysytem