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Title: The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO 2 Working Fluid

A multi-stage centrifugal compressor model is presented with emphasis on analyzing use of an exit flow coefficient vs. an inlet flow coefficient performance parameter to predict off-design conditions in the critical region of a supercritical carbon dioxide (CO 2) power cycle. A description of the performance parameters is given along with their implementation in a design model (number of stages, basic sizing, etc.) and a dynamic model (for use in transient studies). A design case is shown for two compressors, a bypass compressor and a main compressor, as defined in a process simulation of a 10 megawatt (MW) supercritical CO 2 recompression Brayton cycle. Simulation results are presented for a simple open cycle and closed cycle process with changes to the inlet temperature of the main compressor which operates near the CO 2 critical point. Results showed some difference in results using the exit vs. inlet flow coefficient correction, however, it was not significant for the range of conditions examined. Here, this paper also serves as a reference for future works, including a full process simulation of the 10 MW recompression Brayton cycle.
 [1] ;  [1]
  1. National Energy Technology Lab. (NETL), Morgantown, WV (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 9999-0011
Accepted Manuscript
Journal Name:
ASME Turbomachinery Technical Conference and Exposition
Additional Journal Information:
Journal Volume: 9; Conference: ASME Turbo Expo 2017, Charlotte, NC (United States), 26-30 Jun 2017; Related Information: GT2017-63090; Journal ID: ISSN 9999-0011
Research Org:
National Energy Technology Laboratory, Pittsburgh, PA, and Morgantown, WV (United States)
Sponsoring Org:
Country of Publication:
United States
42 ENGINEERING; supercritical CO2; compressor; dynamic mode; flow (dynamics); fluids; impellers; design
OSTI Identifier: