Analytical Evaluation of 2-stage Pusher Centrifuge Dynamic Performance

Document Type : Original Article

Author
Mehdi Jafari Vardanjani
Assistant Professor, Department of Mechanical Engineering, National University of Skills (NUS), Tehran, Iran
10.22034/stme.2024.481489.1080
Abstract
Mechanical filtration of solid and liquid phases with the help of centrifuge mechanism is a common operation in industries particularly for salt dehydration. The process is mainly based on the centrifuge action between particles and fluids. Currently most of the studies have been performed on single-stage centrifuges while there it is required to know and analyze the behavior of the multi-stage pusher centrifuges in order to optimize their efficiency. The structure and dynamic performance of the two-stage pusher centrifuge device has been analyzed in the current study in three phases: modal, particle behavior, and transient state dynamics analysis. The results of the modal analysis have demonstrated that the safety margin obtained in the context of the resonance occurrence for the internal basket set and subset due to linear and rotational inertial forces has been 40%. Based on the results of the transient dynamics analysis, the stability of the particle behavior has been about 5.5 s or 68% of the particle feeding time, the maximum displacement at the critical point of the inner basket subset has been 0.51 mm, and the critical stress value has been about 27 MPa; which has been acceptable in terms of mechanical strength of the assembly versus the stresses and strains caused by the operation of the device. Thus, it is recommended based on the results to maintain the maximum rotational motion (36.68 rad/s) and no significant change in the particle feeding rate compared to the specified value (0.56 kg/s).
Keywords
Pusher centrifuge
Dynamic analysis
Modal analysis
Subjects
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  • Receive Date 06 October 2024
  • Revise Date 01 December 2024
  • Accept Date 31 December 2024
  • First Publish Date 31 December 2024
  • Publish Date 21 September 2024