Numerical Simulation of Gas - Solid Cyclone Separators Operating at High Temperatures

Although cyclones have simple geometries their flow is really complicated. Inlet fluid temperature is one of the factors that increases its complexity. Variation of the thermo-physical properties of the working fluid with temperature causes cyclones to have different pressure drop and particle separation efficiency. In this paper, the effect of fluid and particles temperature on two main performance parameters (pressure drop and separation efficiency) of low-mass-loading Stairmand high efficiency cyclone are numerically investigated. Eulerian-Lagrangian approach is used to model twophase flow. Simulation is performed at a temperature range of 293-700 K and four inlet velocities. Also, the turbulent equations are solved with unsteady Reynolds stress method. Results show that increasing in dynamic viscosity due to increase in fluid temperature, causes increment in shear stress in cyclone body. Therefore, separation efficiency and pressure drop are decreased. If the inlet flow temperature increases by 100 K, pressure drop decreases between 14% and 16% at different inlet velocities. Also, separation efficiency is decreased by 4.64% between the minimum and maximum of inlet temperatures.