Composite Validation

[Raghav]

Hi everyone,

I am facing a problem in validating the composite model for high velocity impacts. My simulations are underpredicting the value. The velocity drop I am getting is significantly lower compared to the existing literature. I have used solid (MAT_59) and shell (MAT_54) elements with quater model. SPC node set boundary onditions were provided with x (1 0 0 0 1 1) and y (0 1 0 1 0 1) symmetry. EFFEPS and VOLEPS is set for solid elements as erosion criteria. For shell, DFAILM, DFAILT, DFAILC, DFAILS are taken as failure criteria. 

Eroding surface to surface contact is used between projectile and target whereas automatic surface to surface tiebreak contact is used for contacts between layers with option 4 for both the models. Soft constraint is used (SOFT=1). I can provide the material properties if needed. 

Please guide me where I am making a mistake.

Thankyou