Elastic and Visco-Plastic Materials
With FLOW-3D’s elastic stress model, it is possible to simulate the transient response of elastic-visco-plastic materials, which are materials that behave as elastic solids up to a certain yield stress, beyond which they behave like a viscous liquid. The elastic stress is computed incrementally from one time step to the next, which makes it easy to simulate large deformations.
One example of this is the ability is to simulate the behavior of purely elastic bodies. For example, a rubbery ball, 4cm in diameter, whose elastic modulus is 10kPa and density is 1g/cm3, is bounced off a solid surface.
Another example is that of a viscoplastic, or Bingham, material being forced through a cylindrical die by a uniform pressure gradient, as shown below. The material has an elastic modulus of 1kPa and a yielding stress of 0.1kPa and is forced through a 1cm diameter die.