Moving particle semi-implicit method


The moving particle semi-implicit method is a computational method for the simulation of incompressible free surface flows. It is a macroscopic, deterministic particle method developed by Koshizuka and Oka.

Method

The MPS method is used to solve the Navier-Stokes equations in a Lagrangian framework. A fractional step method is applied which consists of splitting each time step in two steps of prediction and correction. The fluid is represented with particles, and the motion of each particle is calculated based on the interactions with the neighboring particles by means of a kernel function. The MPS method is similar to the SPH method in that both methods provide approximations to the strong form of the partial differential equations on the basis of integral interpolants. However, the MPS method applies simplified differential operator models solely based on a local weighted averaging process without taking the gradient of a kernel function. In addition, the solution process of MPS method differs to that of the original SPH method as the solutions to the PDEs are obtained through a semi-implicit prediction-correction process rather than the fully explicit one in original SPH method.

Applications

Through the past years, the MPS method has been applied in a wide range of engineering applications including Nuclear Engineering, Coastal Engineering, Environmental Hydraulics, Ocean Engineering, Structural Engineering, Mechanical Engineering, Bioengineering and Chemical Engineering.

Improvements

Improved versions of MPS method have been proposed for enhancement of numerical stability, momentum conservation, mechanical energy conservation, pressure calculation, and for simulation of multiphase and granular flows.