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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

Abstract

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.

Authors:
 [1];  [1]
  1. National Energy Technology Lab. (NETL), Morgantown, WV (United States)
Publication Date:
Research Org.:
National Energy Technology Laboratory, Pittsburgh, PA, and Morgantown, WV (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1395135
Report Number(s):
NETL-PUB-20734
Journal ID: ISSN 9999-0011
Resource Type:
Journal Article: 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
Publisher:
ASME
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; supercritical CO2; compressor; dynamic mode; flow (dynamics); fluids; impellers; design

Citation Formats

Liese, Eric, and Zitney, Stephen E. The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO2 Working Fluid. United States: N. p., 2017. Web. doi:10.1115/GT2017-63090.
Liese, Eric, & Zitney, Stephen E. The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO2 Working Fluid. United States. doi:10.1115/GT2017-63090.
Liese, Eric, and Zitney, Stephen E. Mon . "The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO2 Working Fluid". United States. doi:10.1115/GT2017-63090.
@article{osti_1395135,
title = {The Impeller Exit Flow Coefficient As a Performance Map Variable for Predicting Centrifugal Compressor Off-Design Operation Applied to a Supercritical CO2 Working Fluid},
author = {Liese, Eric and Zitney, Stephen E.},
abstractNote = {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 (CO2) 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 CO2 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 CO2 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.},
doi = {10.1115/GT2017-63090},
journal = {ASME Turbomachinery Technical Conference and Exposition},
number = ,
volume = 9,
place = {United States},
year = {Mon Jun 26 00:00:00 EDT 2017},
month = {Mon Jun 26 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on June 26, 2018
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