Loading...

Design, Optimization and Numerical and Experimental Investigation of the Impeller of a Centrifugal Compressor under Geometric Constraints

Moussavi Torshizi, Abolfazl | 2017

1650 Viewed
  1. Type of Document: Ph.D. Dissertation
  2. Language: Farsi
  3. Document No: 49556 (08)
  4. University: Sharif University of Technology
  5. Department: Mechanical Engineering
  6. Advisor(s): Hajilouy Benisi, Ali; Durali, Mohammad
  7. Abstract:
  8. Centrifugal compressors are vastly implemented in the industry due to their higher pressure ratio per stage. So, researches are still going on to improve the performance of these devices. On this way, the current project is defined to perform geometrical optimization in the impeller of a centrifugal compressor using numerical and experimental methods. In this research, the design process of centrifugal compressors is first discussed according to methods and guidelines provided in several references. Then the compressor of the GT4082 turbocharger is redesigned using these theories. It is shown that overall available rules are enough to design an acceptable centrifugal compressor. Experimental and numerical data presented in the literature, show that flow does not follow blade shapes in the passages of the impeller. Thus, splitter blades encounter high incidence angle and the performance is impaired due to related losses. To alleviate this problem, the shape of splitter blades is optimized by two different methods using genetic algorithm in conjunction with 3D numerical models.In the first method, the position of the leading edge of splitter blades is varied. In the second method, the profile of splitter blade is optimized without altering the position of the leading edge. After performing rigorous aerodynamic and structural simulations to assure the performance and safety of designs, impellers are manufactured with five axis CNC machines. Finally, impellers are mounted on compressor shaft and tested at different conditions in the turbocharger lab.Results showed a maximum of 2.1 point improvement in efficiency and 30% in surge margin for the first impeller. The second concept presented maximum 3.3 point improvement in efficiency. The pressure ratio was almost preserved in all designs
  9. Keywords:
  10. Centrifugal Compressor ; Optimization ; Impeller Speed ; Splitters ; Splitter Blades ; Incidence Loss

 Digital Object List

 Bookmark

...see more