Assignment 7-Side Pole Crash Simulation Challenge

AIM: Car side crash analysis by using Hypermesh and hypercrash.

Objective:

• Check unit system and either follow [Mg mm s] or [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.
• Compare the model weight with the referance model and use added masses to reach target weight 700kg while getting CG about the required range.
• Initial velocity as shown in picture.
• Use model checker to ensure good quality.
• Timestep :0.5 to 0.1 microseconds.
• Run 80ms.

Firstly import the model in hypermesh.check the unit system kg,mm,ms.go to tab bar and select the model browser-begin card see the units .

• create the interface with friction 0.2 go to solver browser-inter-create-type7

• Next create the rigid wall go to select model browser-create-rigidwall

• need to add mass to reach weight of 700kg.
• solver browser-select add mass-create.

• create a node taking above as values.
• menu bar.Geom-nodes

• create a sectional force in the cross member.

• create frame on the cross member.
• solver browser-create-frame-mov

• create a intrusion at B_pillar,hinge pillar and fuel tank.
• 1d-springs
• select nodes and create spring at B_pillar,hinge,fuel tank.
• create a properties and assign them to spring.
• solverbrowser-create-boundary condition-INIVEL -

KINEMATIC ENERGY:

kinetic energy, form of energy that an object or a particle has by reason of its motion. If work, which transfers energy, is done on an object by applying a net force, the object speeds up and thereby gains kinetic energy. Kinetic energy is a property of a moving object or particle and depends not only on its motion but also on its mass. The kind of motion may be translation (or motion along a path from one place to another), rotation about an axis, vibration, or any combination of motions.

INTERNAL ENERGY:

Every substance possesses a fixed quantity of energy which depends upon its chemical nature and its state of existence. This is known as intrinsic energy. Every substance has a definite value of internal energy and is equal to the energies possessed by all its constituents namely atoms, ions or molecules.

The change in internal energy which occurs during chemical reactions. The change in internal energy of a reaction may be considered as the difference between the internal energies of the two states.

Let E_A and E_b are the initial energies in states A and B respectively. Then the difference between the initial energies in the two states will be

ΔU = E_B – E_A

TOTAL ENERGY:

The total energy of a system is the sum of kinetic and gravitational potential energy, and this total energy is conserved in orbital motion. ... Objects with total energy less than zero are bound; those with zero or greater are unbounded.

OUTPUT:

• The main purpose of simulations of the front crash simulation is to occupied of the safety and damage controls.
• As created of cross-section,frames,intrusion and initial velocity and accelerometer.
• Center of gravity: The center of gravity (cog) of an object is the point at which weight is evenly dispersed and all side are balanced.
• Rigid wall: rigid wll is created in the hypermesh because where the cra is going to make collisions.
• Penetrations: There should not be any penetration because nodes get penetrated in the elements and caused failures in simulations,removal of penetrated nodes is necessary.
• Intrusion: Intrusion is used to chesk that is the component is withstanding a crash makig sure that the componernts doest not fail.
• Cross section: To maintain the equivalent forces distribution in car.

Conclusion:

Side crash analysis was carried out on the given BIW model .The output requested were also generated aftre creation of cross-section in each of those regions.

Peak velocity and intrusion values are also measured.Fuel tank intrusion and intrusion in general could be reduced by using anti-intrusion beams between the pillars.They can be increased the rigidity of the door and distributed energy in the event of side-on crash.