Design of compact intermediate heat exchangers for gas cooled fast reactors

Two aspects of an intermediate heat exchanger (IHX) for GFR service have been investigated: (1) the intrinsic characteristics of the proposed compact printed circuit heat exchanger (PCHE); and (2) a specific design optimizing economic and technical efficiency while coupling a supercritical CO2 Brayton power cycle to a helium cooled fast reactor core. In particular, the wavy channel friction factor and the effective conduction thickness between channels were evaluated by simulations using state of the art software (FluentTm). To support the competitiveness of the PCHE, it was directly compared to other potential IHX candidates with respect to performance and size for identical operating conditions. All PCHE modeling conservatively assumed straight channels and was carried out using an MIT in-house code. The PCHEs designed specifically for the He/S-CO2 cycle were designed to be deployed in a prestressed cast iron reactor vessel (PCIV) pod and to permit a net cycle efficiency of at least 40%. Optimization theory, sensitivity studies, and thermal-hydraulic constraints contributed to shaping the final design. The friction factor analysis showed that the correlations cited in the literature overestimate the value by approximately a factor of two. As regards the effective conduction thickness ratio, it was found to be around 0.6 for a 2.0 mm channel diameter. Since the value of the ratio employed in the MIT in-house code is 1.0, the results generated by the code should be conservative.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Nuclear Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2004

Author dc:creator

• Gezelius, Knut, 1978-

Advisor dc:contributor.advisor

• Michael J. Driscoll and Pavel Hejzlar.

• Nuclear Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/26911

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/26911