Velocity of solid particles in aero-mixture channel has been recognized as the most significant factor that has an influence on erosion. In this paper, numerical study of particle erosion in aero-mixture channel was conducted due to the main parameters that have the greatest impact. Pulverised coal boiler OB650 is supplied with an aero-mixture (pulverised coal and flue gases) through distribution channels, 2358 Amel Mešić et al. where the distribution of the same aero-mixture is regulated with a tilt of regulation dumper. These types of regulation cause the problems that have greater impact on the internal structure of the same distribution channels. It is concluded that the best way to determinate that problems is with CFD tool. In this case CFD tool was used to simulate the flow field inside the channel, using Euler-Lagrangian mathematical approach.