Side crash of simpified car s BIW model using HYPERMESH

OBJECTIVE:

The objective of this assignment is to perform a side crash analysis for the given simplified car model and observe the sectional forces and displacements and energies.

PROCEDURE:

• CREATE INTERFACE ----- As to create the interface of type7 which is the most appropriate suitable interface used over for all crash analysis so that it is assigned with recommended parameters as followed.
• CREATE RIGIDWALL ----- As the crash analysis requires the rigid wall that car is imposed with velocity as it moves with a certain velocity and the crashing the rigid wall so as due to the crash of the car and the deformation and the energies transformation through the structure of the car model can be analyzed. The rigid wall is created with the friction of 0.1.
  • Create a rigid wall of an infinite cylinder normal to the z-axis with (2250,1020,2000)

  Dsearch=1000mm

  Diameter=254mm

  Fric=0.1

• MASS BALANCING----- As for this frontal crash the mass of the simplified car model is preferred to be a range of 700kg. and after the mass addition, the Centre of gravity is also to be maintained as below to floor of the model. The mass is added to the model from 188 kg to 700 kg and the COG is maintained at the center.
  • Model weight is equal to the full-scale model weight of 700 kg and COG lies on seat reinforcement.
• ASSIGNING THE INITIAL VELOCITY ----- As the car is about to crash at the speed of 35mph. so that by assigning the INIVEL boundary conditions to the car model as it inerts the model to move at speed of 35mph.Took initial velocity as 15.646mm/ms in y-direction because impact happens in this direction and run the simulation for 80ms with a frequency of 5ms.
• OUTPUT REQUESTS
  • The output request is defined by creating the TH/SECT card for the particular cross-section.
  • As the sectional force is to be noted down at sectional area around the rail part below the seat reinforcement and the intrusion is observed for B-pillar, Hinge pillar and fuel tank region.
  • To observe the peak velocity of any node present in the inner part of the door.

OUTPUT:

• Sectional forces on the cross-members
  • As in this crash analysis, the cross-section created at two cross member are observed that the one cross member at the front has more mass than the other so resultant force at these two cross member is varied due to internal energy stored in the crossection2 is high so that the force required to deform that cross member is high.

• Intrusions at B-pillar, Hinge pillar and fuel tank region
  • As the crash happens the intrusion of the certain node lies on each part to be observed is calculated.

Measurement at start Measurement after intrusion

• Peak velocity of the inner node of the door:
  • The peak velocity on the inner node of the door is 17.11mm/ms at 9.3ms

Conclusions:

The side crash simulation of the simplified car model was successfully performed by giving input conditions. The results obtained for certain conditions as specified in the assignment.