Loading...

The Study of Flow with Suspended Solid Particles through a Centrifugal Fan to Avoid Asymmetric Erosion of the Impeller and its Redesign to Improve its Endurance

Mirzakhani, Hossein | 2022

84 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 56002 (45)
  4. University: Sharif University of Technology
  5. Department: Aerospace Engineering
  6. Advisor(s): Darbandi, Masoud
  7. Abstract:
  8. Industrial centrifuge fans operate in various industries, specifically heavy industries such as pelletizing plants, steel mills, and cement plants. These fans transfer process gas in the production cycle. In some cases, due to their off-design working conditions, asymmetrical wear and failure happen on one side of the impeller's blades more than the other side. The most important reason is the heterogeneity of the entrance fluid's properties. One of the many critical parameters in this issue is the asymmetric distribution of particles between the two entrances of the fan. This research investigates the asymmetric erosion problem of a specific centrifugal fan with a double-suction side impeller by using numerical tools to analyze the two-phase flow (gas-solid) and provide a solution. In this problem, the volume fraction of dust particles is meager concerning the fluid, so the assumption of ignoring the effect of the solid phase on the gas phase is acceptable. For this reason, the path of suspended solid particles has been tracked by numerical models developed based on the Lagrangian method. In this project, fluid is considered an incompressible gas, the k-epsilon model is used to model the turbulence, the Forder model is used to describe the reflective behavior of particles after hitting and reflecting the walls, and the Finnie model is used to give a qualitative estimation of erosion of fan's blades. The Frozen rotor model based on the multiple-reference frames approach has been used to simulate fluid passing through the impellers of the centrifugal fan. Finally, investigations show that the problem occurs because entering fluid from a critical area affects the path of dust particles and deviates them asymmetric with respect to the symmetry plane of the fan. In order to provide a solution, sensitivity analysis is performed on the variables of the incoming mass flow rate from the cold inlets to obtain the most optimal ratio of the incoming mass flow rate from the two cold-inlet channels to reduce the inhomogeneity of the impeller's erosion. For this purpose, many simulations have been performed on the fan's system. In each simulation, the paths of particles are tracked ked, and their erosion effects on the impeller are analyzed. The result of this research offers the best mass flow rate ratio of cold inlets to reduce the heterogeneity erosion of the impeller to a minimum
  9. Keywords:
  10. Centrifugal Fan ; Numerical Simulation ; Life Cycle Model ; Turbulence ; Computational Fluid Dynamics (CFD) ; Two Phase Flow ; Solid Particles ; Impellers

 Digital Object List

 Bookmark

No TOC