This project aimed to investigate the capability of the STAR CCM+ software when predicting the flow with particles using Lagrangian Particle Tracking and Discrete Element Method. The first part pertained to rectangular channel flow, with ratio between height of the channel and particle diameter (2h/Dp ) of 15. It was found out that simulations of particles in a channel come with many diculties. Such as, obtaining accurate pressure drop results using DEM when comparing to DNS simulations including particles within a reasonable computational time. The second part consisted of a simulation of the off-centred mixing tank. As the use of DEM caused numerical issues, another modeling approach was used. Therefore, the Lagrangian Particle Tracking was used. The outcome of the project is the sensitivity study of the forces which can be applied to the particles. The finding was that the Shear Lift force and the Virtual Mass force have a negligible contribution in regards to the particles distribution. In addition to this, it was also discovered that the turbulence model has a large effect on the particles in the near-wall region. Choosing an isotropic turbulence model resulted in clustering of the particles near the wall, therefore an anisotorpic turbulence model needed to be used.