S Balakumaran
Civil/Environmental
I am trying to simulate impact analysis with Car and Crash Barrier in ABAQUS. I used SI (mm) units throughout my modeling. When I run my model, I encounter the following error - “The ratio of deformation speed to wave speed exceeds 1.0000 in at least one element”. The stepwise procedure given in my model are given below:
Material Property:
Car: Mass Density : 2.5e-9 tonne/mm^3 ; Elasticity: 70000 MPa ; Poisson Ratio : 0.3
Crash Barrier: Mass Density : 7.8e-9 tonne/mm^3 ; Elasticity: 210000 MPa ; Poisson Ratio : 0.3
Step: Dynamic Explicit
Basic: Time Period: 0.05
Incrementation: Time Scaling factor: 0.2
Interaction: General Contact (Explicit)
Load: Predefined Field - Velocity: 10000 mm/s
Mesh size: Car – 50 ; Crash Barrier - 100
I developed this model based on this Youtube video - Since I encounter deformation speed error in the above model, I tried to simulate impact analysis with Car and Steel Column as explained in Youtube. This time, I followed the same steps as above except Predefined field – Velocity : 60000 mm/s. The model runs well without any error.
Comparing both the models, the only difference is velocity. In my study, the velocity is 10000 mm/s, whereas in the Youtube video, it is 60000 mm/s. While so, Why should I encounter the deformation speed error? What should I do to correct this error? Your suggestions are most welcomed.
Material Property:
Car: Mass Density : 2.5e-9 tonne/mm^3 ; Elasticity: 70000 MPa ; Poisson Ratio : 0.3
Crash Barrier: Mass Density : 7.8e-9 tonne/mm^3 ; Elasticity: 210000 MPa ; Poisson Ratio : 0.3
Step: Dynamic Explicit
Basic: Time Period: 0.05
Incrementation: Time Scaling factor: 0.2
Interaction: General Contact (Explicit)
Load: Predefined Field - Velocity: 10000 mm/s
Mesh size: Car – 50 ; Crash Barrier - 100
I developed this model based on this Youtube video - Since I encounter deformation speed error in the above model, I tried to simulate impact analysis with Car and Steel Column as explained in Youtube. This time, I followed the same steps as above except Predefined field – Velocity : 60000 mm/s. The model runs well without any error.
Comparing both the models, the only difference is velocity. In my study, the velocity is 10000 mm/s, whereas in the Youtube video, it is 60000 mm/s. While so, Why should I encounter the deformation speed error? What should I do to correct this error? Your suggestions are most welcomed.
