Separation Technology,
Saeed Ovaysi
Abstract
A new approach is proposed to evaluate various designs for gas-solid cyclone separators. This approach uses single-phase flow simulation results to find a quantitative measure of flow symmetry in a given cyclone. Flow symmetry is computed by averaging imbalances of non-axial velocities ...
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A new approach is proposed to evaluate various designs for gas-solid cyclone separators. This approach uses single-phase flow simulation results to find a quantitative measure of flow symmetry in a given cyclone. Flow symmetry is computed by averaging imbalances of non-axial velocities throughout the cyclone. Using this approach, two standard design methods are evaluated and the cyclone with a more symmetric flow pattern is chosen as a starting point for further design improvements by reducing the diameter of its vortex finder. Two-phase computational fluid dynamics (CFD) simulations compute 90.2 % collection efficiency for the improved design. CFD simulations reveal using a cascade of four cyclones results in an overall 99.98 % collection efficiency. Once installed in the actual industrial setting, the cyclone cascade achieves a 98.56 % collection efficiency and a particle size distribution which is in good agreement with CFD computed results.
H. Rezaei; S. Ovaysi; M. Rahimi
Abstract
The objective of the investigation was to mathematically correlate the behavior of a supersonic superheated steam flow inside a Laval nozzle, against the decision parameters. The decision parameters are the inlet temperature ranging from 374.3 K to 504.3 K and the inlet pressure from 40050.14 Pa to 133375.7 ...
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The objective of the investigation was to mathematically correlate the behavior of a supersonic superheated steam flow inside a Laval nozzle, against the decision parameters. The decision parameters are the inlet temperature ranging from 374.3 K to 504.3 K and the inlet pressure from 40050.14 Pa to 133375.7 Pa. Indeed, the outlet temperature, outlet pressure as well as the Mach number are mathematically correlated against the decision parameters. The numerical approach based on the Computational Fluid Dynamics (CFD) is selected to study the behavior of the supersonic superheated steam flow inside the nozzle. By examining the different temperature and pressure conditions of the inlet fluid, it was found that the closest distance from the starting point of condensation to the throat is at the highest pressure and lowest temperature. Conversely, the farthest distance from the starting point of condensation to the throat is at the lowest pressure and highest temperature. In addition, three mathematical correlations were developed. Due to the high accuracy of the mathematical correlations, the efficiency of the predictor models in predicting the outputs was proved.