Input Files

Introduction

It is possible to have Solid elements break into SPH particles using ‘Sol2SPH’ method in OpenRadioss for simulation of high deformation of solid structures.

In this simple demonstration model, solid elements become SPH particles when a /FAIL/TENSSTRAIN criteria is reached

Options and Keywords Used

Keyword documentation may be found in the reference guide available from

OpenRadioss User Documentation

/FAIL/TENSSTRAIN
/MAT/PLAS_JOHNS
/PROP/TYPE34 (SPH)
/INIVEL

Model Description

A rigidised steel ball of approx 1kg mass and 13.5mm diameter impacts a 5mm thick solid aluminium plate modelled with 3 solid elements through the thickness at a a velocity of 100000 mm/s

Units: mm, s, T, N, MPa

The model has following characteristics.

Model Method

The property of the solid elements (Belonging to PART 1) refers to a 2nd SPH part (PART 5) into which eroded solid elements are ‘converted’ on erosion

/INIVEL/TRA is used to set ball with initial velocity 100000 mm/s
An /INTER/TYPE19 is defined between the ball and plate
Other remarks
The animation out uses both /ANIM and the H3D format via /H3D. /H3D gives better visualisation of the SPH particles as shown in the screenshots.

Results

As the solid elements are eroded they are replaced by SPH particles per the specification defined in the property ‘Ndir’ (in this case Ndir is set as 2, so 2x2x2 or 8 SPH particles per solid element)

Conclusion

Sol2SPH may be used to represent a solid part experiencing high deformation, converting solid elements to an SPH representation when a failure criterion is met

OpenRadioss

Sol2SPH Ball - Plate Impact