Analysis of various mathematical models of turbulence when calculating the gas dynamics in a classifier with coaxially arranged pipes

Abstract

Abstract This scientific article deals with the problem of choosing the mathematical model for calculating the gas dynamics in a classifier with coaxially arranged pipes. Various mathematical models were analyzed in ANSYS Fluent software package. Laminar, Spalart-Allmaras, k-ω, RSM and Transition SST were considered as mathematical models. The influence of number of cells in the calculation grid on the pressure loss change in the classifier for various mathematical models was also analyzed. The results of study showed that the pressure loss in the classifier with coaxially arranged pipes is not more than 395 Pa at the inlet gas flow rate of 10 m/s. Among the considered models i.e. laminar, Spalart-Allmaras, k-ω, RSM and Transition SST, the most adequate one is Transition SST model. When changing the number of cells in the calculation grid from 1241551 to 3159388 for this model, the deviation of pressure loss in the classifier was 0.43%. The article includes an equation for the dependence of pressure loss in the classifier on the inlet rate. The distribution of gas flow rate over various sections of rectangular gaps is shown.