Assignment 7

Aim :

• 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.
• Sectional force in the cross member.
• Intrusion at B pillar,hinge pillar and fuel tank region.Provide recommendation on what can help to reduce Fuel tank intrusion.
• Peak velocity of inner node of the door.

Solution :

We will be doing the side impact analysis of the following component :

Unit System

Therefore the unit is system is KG,ms , mm as shown above .

Recommended Interfaces :

Type 19:

Type 19 conisders the contact between the nodes as well as the nodes ,hence the energy dissiaption because of the penetration is lower compared to type 7 and type 11 .Hence it is recommended to use Type 19.

Penetration Check :

As you can see there are 112 penetrations .

Using the penetration tool checker ,this can be removed as shown below :

Section Forces :

The sections have been created to analyse the amount of axial force acting on the following components :

Creation of Rigid Wall :

As you can see for side impact a pole is created which is cyclindrical in shape .

The diameter of the pole is 10 inches .

Intrusions :

Intrusion tells us how much deformation has taken place at a particular place in the vehicle .Following intrusions are considered for analysis :

1.Driver Dashboard Intrusion

2.B Pillar Intrusion

3.Fuel Tank Area Intrusion

Addition of Mass :

Comaparing it with the whole car model :

Hence we will be adding mass to the body so that it represents the a realistic case in the side crash

Current Mass :

Hence a mass of 700 kgs is added to the following nodes :

Mass after addition:

Results :

Section forces :

Other Energies :

Displacements at Intrusions :

1.Displacement at Hinge Pillar

These are displacement at all the nodes in this region.

2.Displacement at B Pillar

Errors :

The error can be see the addition of mass so that the time step remains constant as shown below :

As you can see there is a mass error of 8% ,hence there is an addition of mass to the system as shown below :

This addition takes place in order to keep the time step constant ,the time step is shown below :

This error can be reduced by increasing the critical time step.