Assignment 7

NEON SIDE CRASH ANALYSIS ON BIW MODEL

AIM: To perform a Neon side crash-BIW Analysis of the givein model.

OBJECTIVE:

• Check unit system and either follow [Kg mm ms].
• Create appropriate interface ,friction 0.2 and recommended parameters.
• Make sure of no penetration and intersections.
• Create rigid wall with friction 0.1 as per referance model.
• Initial velocity as shown in picture.
• Use model checker to ensure good quality.
• Timestep :0.5 to 0.1 microseconds.
• Run 80ms.

ABSTRACT:

• Import the BIW model in hypermesh radious profile
• Case setup of the model
• Clear the errors using with hypercrash
• Run the simulation
• Create animation file from Hyperview
• Plot the curves in Hyper graph
• Observe the Results

PROCEDURE:

• Import the model in Hypermesh radious profile.
• Check unit system and follow [Kg mm ms].

INTERFACE TYPE 7:

• Interface TYPE7 is a multi-usage impact interface, modeling contact between a master surface and a group of slave nodes. It is also possible to consider heat transfer and heat friction.
• Go to Model > Create group Name as type7.
• give the friction value o.2. And also give standard parameters.
• Like inacti=6 - Gap is variable with time, but initial gap is adjusted as (the node is slightly depenetrated)
• I del=2 - Node and segment deletion flag
• I stf=4 - Interface stiffness is the minimum of the master and slave stiffness
• I gap=2 - Variable gap + gap scale correction of the computed gap.
• I form=2 - Stiffness (incremental) formulation.
• Gap min=0.5 - Minimum gap for impact activation.
• St min=1 - Minimum stiffness

• check penetrations

Tools > click on CHECK PENETRATION > SLECT GROUPS >tick on TYPE 7 > hit on CHECK

MODEL CHECKEER:

TOOLS > MODEL CHECKER >RADIOUS BLOCK> RUN THE ERRORS

• If we ge any errors import the model in hyper crash and clear thise errors.

PENETRATIOS CHECK:

• Check the elements penetratins in the model. if we get ant elemental penetrations clear with using moving mnode option.
• agao to tools click on the penetration check selct ehe groups type7 and click on the check
• would get no penetration from the model.

Create rigid wall with friction 0.1:

• Rigid wall entities provide a method for treating a contact between a rigid surface and nodal points of a deformable body.

go to SOLVER > CREATE > CYLINDER > CREATE

• Give the vslues in normsl x=0,y=0,z=-1 and D search value is1000.
• GIVE THE FRICTION VALUE 0.1.
• Increase the Zm value for required gap between the car door and rigid wall.

ADD MASS:

• Add masess reach to 700 kg
• while getting COG about the required range

go to SOLVER > CREATE >ADD MASS

• Select the nodes add the required mass .check mass details

INITIAL VELOCITY:

Initialize both translational and rotational velocities on a group of nodes in a given coordinate system.

• • Give the initial velocity 35mph for the car in x direction.
  • Change the mph to mm/ms 35mph=15.64mm/ms
  • create inivel card.

  go to SOLVER > CREATE > BOUNDARY CONDITIONS > INIVEL

  • In inivel card give the veleocity 15.64 in x direction
  • create groud id select the all node and create initial velocity of the car

CREATE CROSS SECTIONS: A section is a set of nodes and a set of elements.

• Sectional force in the cross member.

• SOLVER > FRAME > MOVE >CREATE

  • After that create cross section. go to solver and create section name as apiller select the N1,N2,N3.Nodes and call the frame in frame id tahn select the elements proceed
  • give the `Deltat`=0.1 and `alpha`=1.67

  Solver > create >sect

  • Follow the above procedure and create the all cross sections similarly

INTRUSION: Intrusion describes the time history of the nodes.

• create Intrusion at B pillar,hinge pillar and fuel tank region.

• first create the skew at opposite from the mentoined element.

• than go to out put block and create itrusion and select the node and select the skew id

model > output block >create intrusion

PEAK VELOCITY:

• Create Peak velocity of inner node of the door.
• first create skew id at inner node of the door.go to solver desk create and selct on skew and click on move create skew on the inner door
• SLVER DECK> CREATE > SKEW > move
• after than go to model block and create peak velocity in out put block.select the node at created skew and click on the system and call the skew in out put block.

• go out put block and create cross section and click on entity ids and selectthe all cross section.
• go to model in hypermesh and click on cards and select the Engine run give t stop value is 80
• and select the Anim dt give the time step value is 0.3
• than run the simulation.
• Smulation didnt run .shows the errors.

RECTIFY THE ERRORS:

• Export the model in new folder and Import in Hypercrash rfind the errors and rectify some errors
• go to solver and click on GRshell and check the empty sets manually delete the 3 empty sets rectify the ERROR 534.
• in the model unsupported card is there.deleted the unsupported card.

Unsupported card :on import the few radious cards not supported by engineering solutions are written to the unsupported cardsThis panel can be accesed from thethe menu bar by setup>control caeds. the unsupported card exported with reamaining model.unsupported card stored astext and pointers are not considered

RESULT:

CRASH ANIMATION: The deformation occures more in Front side of the car compare with Back side.

SECTOINALL FORCES:

• For getting the sectional forces on front reinforcement and back reinforcement.go Hyperview and create TH card for getting graphs.

• For the frontal reinforcement the value keeps fluctuating but the max value reches the 3.1KN. At the start the simulation after that decrese across the simulation.

• For the back reinforcement keeps the flctuating its reache max value 8.7KN. at between The 40 to 45 sec.

INTRUSIONS: AT B PILLER,HING PILLER AND FUEL TANK REGION

• We are crate TH card for selecting the particular nodes.
• Resultant displacement graphs for B PILLER,HING PILLER AND FUEL TANK REGION.

• The inteusion value for the HING PILLER Nearly910mm.
• The inteusion value for the B PILLER Nearly 430mm
• The inteusion value for the fuel tank region 300mm

TO Reduce the intrusion of fuel tank region we can use the another material hving high stiffness and high vcapacity of shock absorbing and we can use extra mass.

PEAK VELOCITY:

Peak velocity of inner node of the door:

• We observing the peak velocity beganing of the simulation nearly 15.6mm/ms.
• velocity keeps decrease up to 7.5 after the fluctuation.

ENERGY PLOTS:

• WE all knoe the kinetic energy coverted into the internal energy while crash.
• contact energy is increased due to intersect the elements.
• total energy is decresd.some energy converted into contact energy
• hour glss energy is less.not high

ENERGY ERRORS:

• The energy error starts from -0.1%. ends with -6.2%. Energy error negative it means dissipate the energy during the simulation.
• Mass error=0.01%

Recommendation on what can help to reduce Fuel tank intrusion:

• TO Reduce the intrusion of fuel tank region we can use the another material hving high stiffness and high capacity of shock absorbing and we can use extra mass.
• The design of the side impact beam inside the door can sustain high load with smaller displacement.
• recomand the change the design in this model.add the rails for reduce the fuel tank intrusion.
• increasing the side door streangth by adding anothe intrusion streangth.
• also adding another cross member near the fuel tank we can reduse the intrusion.

CONCLUSION:

• Sucrssfully performed Neon side crash -BIW simulation and folloeind observations was analysed.
• The solver deck was setup as per istructions.
• all out put requests were placed
• the simulation was runn successfullywith acceptable energy error=-6.2% and mass error=0.01%
• TO Reduce the intrusion of fuel tank region we can use the another material hving high stiffness and high vcapacity of shock absorbing and we can use extra mass.
• Peak velocity of the inner door is 15.6mm/ms
• peack cross sectional values of the frontal reinforcement 3.1KN And back reinforcemeb=nt value is 8.7KN
• The inteusion value for the HING PILLER Nearly910mm.B PILLER Nearly 430mm AND Fuel tank region is 300mm.