Institute of Engineering and Computational Mechanics
Smoothed Particle Hydrodynamics
Project Description
Smoothed Particle Hydrodynamics, in short SPH, is a discretization method in
space that is applied to continuum mechanics in particular. Being a meshfree
method based on particles that move along the velocity field of the represented
matter, SPH often offers big advantages over meshbased methods such as Finite
Elements when it comes to free surface flows or high deformations of
elastic materials.
To discretize a partial differential equation using the SPH method, the
considered volume is subdivided. These subdivisions are then reduced to one
point, the so-called particle, which gets all the important values such as
velocity, density but also tension and thermal energy as a mean value taken
over the whole subdivision. Therefore, particles are partial volumes with an
undefined volume expansion, that move along the velocity field of the
represented matter. The spatial functions in the differential equation can now
be approximated by smoothing and summing up the discrete values at the particle positions
using a kernel function, often similar to a Gaussian
function. The approximation's spatial derivatives can be calculated straight
away due to the differentiable kernel function. This leaves an ordinary
differential equation in time that can be solved with one of the many time stepping schemes.