Predicting the Behavior of Solar Dynamic Closed Brayton Cycle Power Conversion Systems

Since space power conversion systems must operate both in the sun and in the earth’s shadow, they seldom encounter design operating conditions. As a consequence, consideration of off-design performance is essential in the preliminary design of these systems. To illustrate the necessity and utility of an off-design system model, this paper presents the results of a study of the solar dynamic closed Brayton cycle power conversion system for use on the NASA Space Station.

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Pressure and Thermal Stress Analyses of a Generation IV Reactor System, Mini-Channel Heat Exchanger

Volume 3: Structural Integrity; Nuclear Engineering Advances; Next Generation Systems; Near Term Deployment and Promotion of Nuclear Energy ◽

10.1115/icone14-89385 ◽

2006 ◽

Author(s):

Bong Yoo ◽

Ronald F. Kulak ◽

Yun-Jae Kim

Keyword(s):

Heat Exchanger ◽

Liquid Metal ◽

Power Conversion ◽

Operating Conditions ◽

Design Parameters ◽

Brayton Cycle ◽

Normal Operating ◽

Conversion System ◽

Mini Channels ◽

Stress Analyses

An advanced power conversion system incorporating a Supercritical Carbon Dioxide (S-CO2) Brayton Cycle for Liquid Metal-Cooled Fast Reactors, can provide much improved cycle efficiency relative to a traditional Rankine cycle. Because of this, current plans for Generation IV reactor systems—like the Liquid Metal-Cooled Fast Reactor—include the use of the S-CO2 Brayton Cycle in the development of a power conversion system. However, a structural issue is raised with the use of a mini-channel heat exchanger because large temperature and pressure differences occur along the passages of the mini-channels during normal and transient operating conditions. The design parameters of the heat exchanger during normal operating conditions (i.e., steady state) are pressures and temperatures at the inlet and outlet of the hot and cold channels, and the average heat transfer coefficients within the mini-channels. In this paper, results are presented from preliminary uncoupled thermal and stress analyses of the heat exchanger based on very simple finite element models and the heat exchanger design parameters. Temperature distributions along the passage ways of the mini-channels are calculated. The stresses resulting from both the pressure load and the thermal load are compared with the ASME Section VIII design requirement. The structural integrity of the simplified heat exchanger model—during normal operating conditions of the S-CO2 Brayton Cycle—is evaluated.

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Multi-Objective Solar Power Conversion System With MGI Control for Grid Integration at Adverse Operating Conditions

IEEE Transactions on Sustainable Energy ◽

10.1109/tste.2020.2981356 ◽

2020 ◽

Vol 11 (4) ◽

pp. 2901-2910

Author(s):

Nirmal Mukundan C. M. ◽

Yashi Singh ◽

Syed Bilal Qaiser Naqvi ◽

Bhim Singh ◽

Jayaprakash Pychadathil

Keyword(s):

Solar Power ◽

Power Conversion ◽

Operating Conditions ◽

Grid Integration ◽

Multi Objective ◽

Conversion System

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Sizing of a recuperative supercritical CO2 Brayton cycle as power conversion system for DEMO fusion reactor based on Dual Coolant Lithium Lead blanket

Fusion Engineering and Design ◽

10.1016/j.fusengdes.2018.06.026 ◽

2018 ◽

Vol 134 ◽

pp. 79-91 ◽

Cited By ~ 4

Author(s):

José Ignacio Linares ◽

Eva Arenas ◽

Alexis Cantizano ◽

José Porras ◽

Beatriz Yolanda Moratilla ◽

...

Keyword(s):

Supercritical Co2 ◽

Fusion Reactor ◽

Power Conversion ◽

Brayton Cycle ◽

Conversion System

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Performance Testing of the Compact APCSE Closed Brayton-Cycle System

ASME 1967 Gas Turbine Conference and Products Show ◽

10.1115/67-gt-34 ◽

1967 ◽

Cited By ~ 1

Author(s):

J. M. Janis ◽

G. S. Braun ◽

R. D. Ryan

Keyword(s):

Power Conversion ◽

Performance Testing ◽

Primary System ◽

Brayton Cycle ◽

Test Results ◽

Primary Loop ◽

Cycle System ◽

Conversion System ◽

System Components ◽

Performance Effects

A description of the Advanced Power-Conversion Skid Experiment (APCSE), a 300-kw operating closed Brayton-cycle power-conversion system, is presented. The methods used to predict the performance of the primary-system components and the comparison of these predictions with test results are discussed. Cycle power limitations resulting from deficient performance of some of the primary-loop components, as well as secondary performance effects due to the physical proximity of components, are also discussed.

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Experimental Investigation of a Single Stage Helium Axial Compressor of HTGR-10 Power Conversion Unit

Volume 7: Education; Industrial and Cogeneration; Marine; Oil and Gas Applications ◽

10.1115/gt2008-50921 ◽

2008 ◽

Author(s):

Rongkai Zhu ◽

Qun Zheng ◽

Jiguo Zou ◽

Rakesh Bhargava

Keyword(s):

Experimental Investigation ◽

Power Conversion ◽

Axial Compressor ◽

Operating Conditions ◽

Working Fluid ◽

Brayton Cycle ◽

Flow Conditions ◽

Air Compressor ◽

Conversion Unit ◽

Compressor Performance

This paper focuses on an experimental investigation of a helium compressor, a major component of the Power Conversion Unit (PCU), used in a High Temperature Gas Cooled Reactor (HTGR). The PCU system uses a direct Helium Brayton cycle for the power conversion. In this configuration, there is a strong coupling between the helium compressor and the other components of the PCU system. The estimations of compressor performance in stable and transient operational states are of high importance for the designer. Because of the difficulties in testing a compressor with helium as a working fluid, simulations methods using air to replace helium as a compressor working fluid in the experiments are researched. An experimental compressor system is built to investigate the performance of a helium compressor. Under different operating conditions, the compressor performance characteristics are obtained and compared with that of an air compressor. The possibility and the effective approach of designing a helium compressor based on the experimental data of an air compressor are studied. The experimental results showed that air under the correct flow conditions, identified using similitude analysis, can be used to test a helium compressor instead of far more expensive helium.

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