OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 25 No. 4 2023 formation of a heterogeneous jet, ultimately altering the wear profile of the surface. This study introduces particles have a range of 2–63 µm, with a preference towards smaller diameters. Thus, this paper aims to examine the approach to CFD modelling of a particular scenario in which a highvelocity, heterogeneous jet with a significantly non-uniform particle size distribution flows onto a Ti6Al4V sample. Due to the limited space of this paper, the goals include studying how the choice of turbulence models and its adjustment coefficients, the selection of erosion models and its adjustment coefficients, as well as the influence of particle shape, affect the modelled wear rate. In addition, the selected approach’s performance is evaluated by comparing integral values of the calculated and experimental erosion rates, as well as by comparing the calculated specific erosion rate profiles and the experimental material entrainment profile. Research methodology Experiment For the purposes of this study, we utilized a laboratory experimental bench to examine surface erosion under the influence of heterogeneous flow. The operational principle involved introducing quartz particles into the mixing chamber, from where a mixture of gas (in this instance – air) and particles then was feed into the accelerator. The accelerator, which is a Laval nozzle, enabled the heterogeneous flow to accelerate under the action of pressure difference and impinge on the stationary sample. The significant parameters that define the experimental point were the pressure at the accelerator inlet and the initial gas temperature. This configuration enables the examination of wear under various particle flow angles, temperatures, and velocities. The observed test outcomes were the shape of the crater and the loss of the sample material. These results aid in quantifying the wear rate. The flow rate of particles at each experimental point was 7.64e-6 kg/s for 5 minutes, with a temperature of 140 °C and accelerator pressure of 5.75 bar. The accelerator cut-off was positioned 20 mm away from the sample at a 90° angle to the accelerator position. Fig. 1 displays the size distribution of SiO2 particles. The spectrum was mainly dominated by minute fractions, with the highest equivalent particle diameter of 63 μm. Problem formulation and geometric model Owing to insufficient experimental data on the flow and particle velocity distribution in accelerator regions during the flow onto the sample, the entire accelerator had to be modelled. This was done in order to adequately take into account the variables when estimating the erosion rate. To achieve this, an integral Fig. 1. Particle size distribution
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