Study of the Effect of the Contra-Rotating Component on the Performance of the Centrifugal Compressor

Authors: Van Thang Nguyen, Amelie Danlos, Richard Paridaens, Farid Bakir

Abstract:

This article presents a study of the effect of a contra-rotating component on the efficiency of centrifugal compressors. A contra-rotating centrifugal compressor (CRCC) is constructed using two independent rotors, rotating in the opposite direction and replacing the single rotor of a conventional centrifugal compressor (REF). To respect the geometrical parameters of the REF one, two rotors of the CRCC are designed, based on a single rotor geometry, using the hub and shroud length ratio parameter of the meridional contour. Firstly, the first rotor is designed by choosing a value of length ratio. Then, the second rotor is calculated to be adapted to the fluid flow of the first rotor according aerodynamics principles. In this study, four values of length ratios 0.3, 0.4, 0.5, and 0.6 are used to create four configurations CF1, CF2, CF3, and CF4 respectively. For comparison purpose, the circumferential velocity at the outlet of the REF and the CRCC are preserved, which means that the single rotor of the REF and the second rotor of the CRCC rotate with the same speed of 16000rpm. The speed of the first rotor in this case is chosen to be equal to the speed of the second rotor. The CFD simulation is conducted to compare the performance of the CRCC and the REF with the same boundary conditions. The results show that the configuration with a higher length ratio gives higher pressure rise. However, its efficiency is lower. An investigation over the entire operating range shows that the CF1 is the best configuration in this case. In addition, the CRCC can improve the pressure rise as well as the efficiency by changing the speed of each rotor independently. The results of changing the first rotor speed show with a 130% speed increase, the pressure ratio rises of 8.7% while the efficiency remains stable at the flow rate of the design operating point.

Keywords: Centrifugal compressor, contra-rotating, interaction rotor, vacuum.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.3298874

References:

[1] R. H. Young. Counter rotating fans. JHIVE, 18, (1952).
[2] Ward W. Wilcox. An analysis of the potentialities of a two-stage counter-rotating supersonic compressor. (1952).
[3] P. B. Sharma and A. Adekoya. A review of recent research on contra-rotating axial flow compressor stage. In ASME 1996 International Gas Turbine and Aero engine Congress and Exhibition, pages V001T01A073V001T01A073. American Society of Mechanical Engineers, (1996).
[4] P. B. Sharma, Y. P. Jain, N. K. Jha, and B. B. Khanna. Stalling behavior of a contra-rotating axial compressor stage. In International Symposium on Air Breathing Engines, 7th, Beijing, Peoples Republic of China, pages 734740, (1985).
[5] A. Furukawa, T. Shigemitsu, and S. Watanabe. Performance test and flow measurement of contra-rotating axial flow pump. Journal of Thermal Science, 16(1):713, (2007).
[6] J. Fukutomi, T. Shigemitsu, T. Yasunobu. Performance and internal flow of sirofoilcco fan using contra-rotating rotors. Journal of Thermal Science, 17(1), 3541, (2008). https://doi.org/10.1007/s11630-008-0035-8.
[7] L. Moroz, P. Pagur, Y. Govorushchenko and K. Grebennik. Comparison of counter rotating and traditional axial aircraft low-pressure turbines integral and detailed performances. In Int. Symp. On Heat Transfer in Gas Turbine Systems, (2009).
[8] H. Nouri, A. Danlos, F. Ravelet,F. Bakir, C. Sarraf. Experimental Study of the Instationary Flow Between Two Ducted Counter-Rotating Rotors. Journal of Engineering for Gas Turbines and Power, 135(2), 22601, (2013). https://doi.org/10.1115/1.4007756.
[9] S. Tosin, A. Dreiss,J. Friedrichs. Experimental and numerical investigation of a counter-rotating mixed-flow single stage pump. ASME Expo 2015, 111, 2015.
[10] H. Pitknen,H. Esa, P. Sallinen,J. Larjola. CFD Analysis of a Centrifugal Compressor Impeller and Volute. International Gas Turbine Aeroengine Congress Exhibition, (1997), 18. https://doi.org/10.1115/99-GT-436.
[11] C. Robinson,M. Casey,B. Hutchinson,R. Steed. Impeller-Diffuser Interaction In Centrifugal Compressors, 111, (2011).