Example54 Inelastic Collision

General

  • An object collides with another inelastically. Transient analysis is performed.

  • The same model as Exercise 32: Elastic Collision

  • Large deformation (Large displacement / Large strain) is used.
    See Technical Note Analysis of Large Deformation (Geometric Nonlinearity).

  • The mechanical stresses and the deformations are solved.
     

  • Unless specified in the list below, the default conditions will be applied.

  •  

  •  

 

Analysis Space

Item

Settings

Analysis Space

2D

Model unit

mm

 

Analysis Conditions

To simplify the simulation, the 2D model is created and analyzed.

“Large deformation” is selected, as it is expected.

Item

Settings

Solver

Mechanical Stress Analysis [Galileo]

Analysis Type

Transient analysis

Large deformation

Select both “Large displacement” and Large strain”

 

The transient analysis is set up as follows.

The time steps after the collision are smaller than those before the collision.

Tab

Setting Item

Settings

Transient analysis

Table

Number

Calculation steps

Output steps

Time step [s]

1

10

1

0.1×10^-4

2

80

1

0.025×10^-4

Model

Circular sheet bodies represent objects.

The contactor and contactee surfaces are paired in the “Boundary Pair” dialog box.

Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name

0/Sheet

Body_Attribute_001

ElastoPlastic

1/Sheet

Body_Attribute_002

ElastoPlastic

 

The material of these two bodies is elasto-plastic.

Material Name

Tab

Properties

ElastoPlastic

Elasticity

Material Type: Elasto-plastic/Bilinear

Temperature Dependency: No

Material Property:

Young’s modulus: 1.26×10^9[Pa]

Poisson’s ratio: 0.3

Strain hardening rate : 1.26×10^8[Pa]

Initial yield stress: 1.0×10^7[Pa]

 

 

The initial velocity of the right object is set as follows. That of the left object is 0.

Body Attribute Name

Initial Velocity

Body_Attribute_002

X component: -100[m/s]

Y and Z components: 0[m/s]

Boundary conditions

Boundary Condition Name/Topology

Tab

Boundary Condition Type

Settings

Contactor/Edge

Mechanical

Contact surface

Select “Contactor surface”.

Target/Edge

Mechanical

Contact surface

Select “Contactee surface”.

The contactor and contactee surfaces are designated as a contact pair in the “Boundary Pair” dialog box. In contact analyses, the contact surfaces must be designated as a boundary pair.

Results

The equivalent plastic strain distributions at 1.5e-4[s] and 3.0e-4[s] are shown below.

 

Plastic strains are exhibited around the contact area.

The deformations due to the plastic strains remain even after the collision.

 

The chart below shows the velocities of 2 objects over time.

 

The blue and red plots are for the right and left objects respectively.

The velocity is transferred from the right object to the left at 1.0e-4[s] through 2.0e-4[s].

 

The velocity is not fully transferred unlike [Exercise 32: Elastic Collision].